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The Mathematics Vision Project Scott Hendrickson, Joleigh Honey, Barbara Kuehl, Travis Lemon, Janet Sutorius
© 2017 Mathematics Vision Project Original work © 2013 in partnership with the Utah State Off ice of Education
This work is licensed under the Creative Commons Attribution CC BY 4.0
MODULE 9
Probability
SECONDARY
MATH TWO
An Integrated Approach
Standard Teacher Notes
SECONDARY MATH 2 // MODULE 9
PROBABILITY
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
MODULE 9 - TABLE OF CONTENTS
PROBABILITY
9.1 TB or Not TB – A Develop Understanding Task
Estimating conditional probabilities and interpreting the meaning of a set of data (S.CP.6, S.MD.7+)
READY, SET, GO Homework: Probability 9.1
9.2 Chocolate versus Vanilla – A Solidify Understanding Task
Examining conditional probability using multiple representations (S.CP.6)
READY, SET, GO Homework: Probability 9.2
9.3 Fried Freddy’s – A Solidify Understanding Task
Using sample to estimate probabilities (S.CP.2, S.CP.6)
READY, SET, GO Homework: Probability 9.3
9.4 Visualizing with Venn – A Solidify Understanding Task
Creating Venn diagram’s using data while examining the addition rule for probability (S.CP.6, S.CP.7)
READY, SET, GO Homework: Probability 9.4
9.5 Freddy Revisited – A Solidify Understanding Task
Examining independence of events using two-way tables (S.CP.2, S.CP.3, S.CP.4, S.CP.5)
READY, SET, GO Homework: Probability 9.5
9.6 Striving for Independence – A Practice Understanding Task
Using data in various representations to determine independence (S.CP.2, S.CP.3, S.CP.4, S.CP.5)
READY, SET, GO Homework: Probability 9.6
SECONDARY MATH II // MODULE 9
PROBABILITY - 9.1
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
9.1 TB or Not TB? A Develop Understanding Task
Tuberculosis(TB)canbetestedinavarietyofways,includingaskintest.Ifapersonhas
turberculosisantibodies,thentheyareconsideredtohaveTB.Belowisatreediagramrepresenting
databasedon1,000peoplewhohavebeengivenaskintestforturberculosis.
1. WhatobservationsdoyounoticeaboutTBtestsbasedonthetreediagram?
2. Youmayhavenoticedthat380patientshaveTB,yetnotall380patientswithTBtested
positive.Instatistics,thenotation:“Testednegative|TB”means‘thenumberofpatientswhotestednegative,giventhattheyhaveTB’.DeterminetheprobabilitythatapersonwhohasTBcouldreceiveanegativeresultcomparedtootherswhohaveTB.Whatdoesthismean?
Thisisanexampleofconditionalprobability,whichisthemeasureofanevent,giventhat
anothereventhasoccurred.
CCBYhttps://flic.kr/p/xXebu
Testednegative|notTB558
PatienthasT
B380
Testednegative|TB19
PatientdoesNOThaveTB620
Testedpositi
ve|TB361
Testedpositi
ve|notTB6
2
1
SECONDARY MATH II // MODULE 9
PROBABILITY - 9.1
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
3. Writeseveralotherprobabilityandconditionalprobabilitystatementsbasedonthetree
diagram.
Partofunderstandingtheworldaroundusisbeingabletoanalyzedataandexplainittoothers.
4. Basedontheprobabilitystatementsfromthetreediagram,whatwouldyousaytoafriendregardingthevalidityoftheirresultsiftheyaretestingforTBusingaskintestandthe
resultcamebackpositive?
5. Inthissituation,explaintheconsequencesoferrors(havingatestwithincorrectresults).
6. Ifahealthtestisnot100%certain,whymightitbebeneficialtohavetheresultsleanmore
towardafalsepositive?
7. Isasamplespaceof200enoughtoindicatewhetherornotthisistrueforanentire
population?
2
SECONDARY MATH II // MODULE 9
PROBABILITY - 9.1
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
9.1 TB or Not TB? – Teacher Notes A Develop Understanding Task
Purpose:Thepurposeofthistaskisforstudentstoanalyzeandmakesenseofdata.Studentswill
connecttheirpriorunderstandingsoftreediagramsandfrequencytables(fromearliergrades)to
analyzedatafromatreediagramandexplaintheresultstoothers.Thefocusofthistaskisto
highlighttheinformationrevealedasaresultoftheconditionalprobabilitystatements.Questions
suchas‘Howdoesthesubgroupinformationtellusamorecompletestory?’shouldbeaddressedin
thistask.
Notetoteacher:Throughoutthemodule,studentswillbeanalyzingdatabutwillhaveotherareas
offocus(suchasrepresentations,theadditionrule,andnotation).Therefore,itisimportantthat
thefocusofthistaskisforstudentstomakesenseofthecontextgiventherepresentationandto
write/communicategeneralprobabilitystatementsandconditionalprobabilitystatements.
CoreStandardsFocus:
S.CP.6:FindtheconditionalprobabilityofAgivenBasthefractionofB’soutcomesthatalsobelong
toA,andinterprettheanswerintermsofthemodel.
S.MD.7(+):Analyzedecisionsandstrategiesusingprobabilityconcepts(e.g.,producttesting,
medicaltesting,pullingahockeygoalieattheendofagame).
RelatedStandards:S.CP.3,S.CP.4,S.CP.5
TheTeachingCycle:
Launch(WholeClass):
Startthistaskbysharinghowimportantitistoknowhowtoreadandmakesenseofdata.Inthe
healthcarefield,therearelotsoftestsusedtodeterminewhetherornotapatienthasaninfection
oradisease.Itisalsoimportanttonotethatnotalltestsareaccurate100%ofthetime,whichis
whythereissometimesmorethanonetesttodetermineadiagnosis.Readthedirectionsfromthe
taskandhavestudentsmakeobservationsaboutthetreediagram(question1).Ifstudentsarenot
SECONDARY MATH II // MODULE 9
PROBABILITY - 9.1
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
familiarwiththesymbolusedforconditionalprobabilitythatisgivenonthetreediagram,explain
thistothem(Testedpositive|TBmeans“thenumberofpatientswhotestedpositive,giventhatthey
haveTB”).
Explore(SmallGroup):
Givestudentstimetomakesenseofthediagramindependentlyandthenhavethemworkinpairs
tocreatestatements.Ifagroupseemsstumped,youcanaskquestionslike:
• Whatinformationdoesthisdiagramtellyou?
• IsthisTBtestalways100%accurate?Howdoyouknow?
• Domostpeopletestpositiveornegativebasedontheskintestresults?
• Whatotherinformationcanyoudetermine?
Itisbesttostayawayfromspecificquestionsatthistimeaspartofthistaskisforstudentstomake
senseandinterpretthedatathemselves.Thelowthresholdofthistaskisthatmoststudentsshould
beabletocreatestatementssuchas“36.1%ofthepopulationtestedhaveTBantibodiesandtested
positive”.Asyoumonitor,ifyounoticestudentsarenotwritinganyconditionalstatements,probe
groupsthatarefinishingquicklytoanalyzetheresultsofaspecificbranch.Forexample,‘Whatdo
youknowaboutpatientswhotestpositive,giventhattheyhaveTB?’ortoexplainthedifference,in
context,betweentheseprobabilities:620/1000,62/620and62/1000.Besuretohavestudents
writeouttheirstatementsintheirjournalandnotjustsaythem.Thisassistsstudentsin
communicatingconditionalprobabilities.Iftheyneedprompting,youmaywishtogiveanexample
ortwousingphrasessuchas“outof”or“giventhat”or“If…then”.
Asyouprepareforthewholegroupdiscussion,chooseagrouptochartsomeoftheirstatements
relatedtothetotalnumberofpeoplewhotooktheskintest.Alsoselectstudentstosharetheir
conditionalstatementswhohavearticulatedunderstanding.
Discuss(WholeClass):
Forthewholegroupdiscussion,thegoalisforstudentstobeabletoanswer“Howaccurateisthe
tuberculosis(TB)test?”usingthedataprovidedtowriteprobabilitystatements.Thereareseveral
waystodothis,withthefollowingasonepossibility:
SECONDARY MATH II // MODULE 9
PROBABILITY - 9.1
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
First,havegroupwhochartedstatementsrelatedtothetotalshareandexplaintheirstatements.
Highlightsofthisconversationincluderesultsofcertainaspectsofthesample(percentwhohave
antibodies,percentwhotestpositive,etc.)andthatthetestisaccurate‘most’ofthetime.Whilethis
isgoodinformation,takingadeeperlookcanrevealmoreinformation.Next,sequencethestudents
youselectedearliertosharetheirconditionalstatementsandaskthemwhattheirstatement
reveals.Besureeachstatementisaccurate(notjustcomputation,butalsohowitis
written/spoken),andmaketheappropriateadjustmentsforthosewhoneedit.Duringthispartof
thediscussionisalsoanappropriatetimetointroduceprobabilitynotationasstudentshavelikely
notseenthisinthepast.
Discussionitemsthatyoumaywishtomakesurecomeout:
1. Meaningoferror(falsepositive/falsenegative)andwhythisparticulardataleansmore
towardafalsepositive.
2. Thelawoflargenumbers.Thesamplesizeofthisdatais1,000.Whatdoesthismeanforan
individualwhohasaskintestforTB?
3. Howdoesexploringconditionalprobabilitiesallowforinvestigationoftheaccuracyof
medicaltests?
AlignedReady,Set,Go:ProbabilityRSG9.1
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.1
Mathematics Vision Project
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9.1
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READY
Topic:VennDiagrams,howtocreateandread.
ForeachVennDiagramprovidedanswerthequestions.
1.Howmanystudentsweresurveyed?
2.Whatwerethestudentsasked?
3.Howmanystudentsareinboth
choirandband?
4.Howmanystudentsarenotineither
choirorband?
5.Whatistheprobabilitythata
randomlyselectedstudentwouldbein
band?
ThisVennDiagramrepresentsenrollmentinsomeof
theelectivecourses.
6.Whatdoesthe95inthecentertellyou?
7.Whatdoesthe145tellyou?
8.Howmanytotalstudentsarerepresentedinthe
diagram?
9.Whichelectiveclasshastheleastnumberof
studentsenrolled?
READY, SET, GO! Name PeriodDate
3
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.1
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SET Topic:Interpretingatreediagramtodetermineprobability
Giventhetreediagrambelowanswerthequestionsanddeterminetheprobabilities.Thediagramrepresentsthenumberofplateappearancesduringthefirstmonthofaminorleaguebaseballseason.
10. Howmanytimesdidabattercometotheplateduringthistimeperiod?
11. Basedonthisdata,ifyouarealeft-handedbatterwhatistheprobabilitythatyouwillfacearight-handedpitcher?
12. Basedonthisdata,ifyouarearight-handedbatterwhatistheprobabilitythatyouwillfacealeft-handedpitcher?
13. Whatistheprobabilitythataleft-handedpitcherwillbethrowingforanygivenplateappearance?
14. Whatistheprobabilitythataleft-handedbatterwouldbeattheplateforanygivenplateappearance?
Whatobservationsdoyoumakeaboutthedata?Isthereanyamountthatseemstobeoverly
abundant?Whatmightaccountforthis?
GO Topic:BasicProbability
Findtheprobabilityofachievingsuccesswitheachoftheeventsbelow.
15. Rollinganevennumberonstandardsix-sideddie.
16. Drawingablackcardfromastandarddeckofcards.
17. FlippingacoinandgettingHeadsthreetimesinarow.
18. Rollingadieandgettingafour.
19. Drawinganacefromadeckofcards.
20. Rollingadietwiceinarowandgettingtwothrees.
21. Fromabagcontaining3blue,2red,and5whitemarbles.Pullingoutaredmarble.
4
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.2
Mathematics Vision Project
9.2 Chocolate versus Vanilla A Solidify Understanding Task
Danielleloveschocolateicecreammuchmorethanvanillaandwas
explainingtoherbestfriendRaquelthatsodoesmostoftheworld.Raquel
disagreedandthoughtvanillaismuchbetter.Tosettletheargument,they
createdasurveyaskingpeopletochoosetheirfavoriteicecreamflavor
betweenchocolateandvanilla.Aftercompletingthesurvey,thefollowing
resultscameback:
• Therewere8,756femalesand6,010maleswhoresponded.
• Outofallthemales,59.7%chosevanillaoverchocolate.
• 4,732femaleschosechocolate.
1. Uponfirstobservations,whichflavordoyouthink“won”?_____________________.Writea
sentencedescribingwhatyouseeat‘firstglance’thatmakesyouthinkthis.
2. Raquelstartedtoorganizethedatainthefollowingtwo-waytable.Seeifyoucanhelp
completethis(usingcountsandnotpercentages):
3. OrganizethesamedatainaVenndiagramandatreediagram.
4. Usingyourorganizeddatarepresentations,writeprobabilitiesthathelpsupportyourclaim
regardingthepreferredflavoroficecream.Foreachprobability,writeacomplete
statementaswellasthecorrespondingprobabilitynotation.
Chocolate Vanilla Total
Female 8,756
Male 6,010
Total
CCBYhttps://flic.kr/p/dAmJrc
5
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.2
Mathematics Vision Project
5. Lookingoverthethreerepresentations(treediagram,two-waytable,andVenndiagram),
whatprobabilitiesseemtobeeasiertoseeineach?Whatprobabilitiesarehiddenorhard
tosee?
Highlighted(easiertosee) HiddenTreediagram
Treediagram
Two-waytable
Two-waytable
Venndiagram
Venndiagram
6. Gettingbacktoicecream.Doyouthinkthisisenoughinformationtoproclaimthe
statementthatoneicecreamisfavoredoveranother?Explain.
6
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.2
Mathematics Vision Project
9.2 Chocolate versus Vanilla – Teacher Notes
A Solidify Understanding Task
Purpose:Thepurposeofthistaskisforstudentstointerpretinformationprovidedthatallows
themtomakesenseofandorganizedatainatreediagram,atwo-waytable,andaVenndiagram.
Studentswillsolidifytheirunderstandingofconditionalprobabilitybywritingstatements
supportedbydatacollectedtojustifytheflavoroficecreampreferredbymost.Inthistask,
studentswill:
● Organizedataintoatreediagram,two-waytable,andaVenndiagram
● CalculateprobabilitiesandconditionalprobabilitiesofAgivenBasthefractionofB’s
outcomesthatalsobelongtoA,andinterprettheanswerintermsofthemodel
● Highlightthedifferentrepresentationsandbecomemorefamiliarwithwhateach
representationhighlightsandconceals.
● Continuetobecomemorefamiliarwithprobabilitynotation.
● Makedecisionsaboutmeaningofdata.
CoreStandardsFocus:
S.CP.4:Constructandinterprettwo-wayfrequencytablesofdatawhentwocategoriesare
associatedwitheachobjectbeingclassified.Usethetwo-waytableasasamplespacetodecideif
eventsareindependentandtoapproximateconditionalprobabilities.
S.CP.6:FindtheconditionalprobabilityofAgivenBasthefractionofB’soutcomesthatalsobelong
toA,andinterprettheanswerintermsofthemodel.
RelatedStandards:S.CP.3,S.CP.5,S.MD.6
TheTeachingCycle
Launch(WholeClass):
Beginbyreadingthecontextoftheproblemandthedataprovidedbythesurvey.Havestudents
individuallymakeadecisiontoquestion1.Thisistheir‘estimation’usingtheirfirstimpression
reasoning.Givestudentswaittimetowritetheirfirstimpression.Tolaunchtherestofthetask,
explaintostudentsthattheywillbeorganizingthedataintothethreerepresentations(tree
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.2
Mathematics Vision Project
diagram,Venndiagram,andtwowaytable).Theywillusethisinformationtofurthermakeclaims
regardingthe‘favoriteicecreamflavor’.
Explore(SmallGroup):Asyoumonitor,listenforstudentstomakesenseofthedataprovidedsothattheycancompletethe
treediagram.Allowfortimesothatstudentscandeterminewhatinformationisstillneededand
howtogoaboutfindingthis.Ifafteracoupleofminutesyounoticeagroupthatseemstobestuck
astohowtobegin,askprobingquestionssuchas“Whatpartofthetreediagramneedstostillbe
completed?”followedby“Howcouldyoufindthesolutiontothatpartofthediagram(suchasthe
numberoffemaleswhoprefervanillaicecream)or(thenumberofmaleswhoprefervanillaice
cream)?”Alsolookforthecommonerroragroupcouldmakebycalculating59.7%ofthetotalto
determinethenumberofmaleswholikeVanillaicecream.Toclarify,havethegroupexplainthe
diagramandtheircalculation.Likely,theywillnoticetheirmistakeandrecalculatetofind59.7%of
themalesinsteadofthetotal.Ifnot,askthemtoexplainthemeaningofthebulletpointinthegiven
datathatreads“Outofallthemales,59.7%chosevanillaoverchocolate.”Asstudentsmovefrom
completingonerepresentationtotheothers(tree,Venn,table),listenforexplanationstheyhavefor
determiningvaluesineachrepresentationandanyconnectionstheymakebetween
representations(asyoumonitor,selectstudentstosharebasedontheseexplanations).Belowis
thecompletedtwowaytabletoassistinmakingsurestudentcalculationsareaccurateaswellasa
coupleofprobabilitystatementsstudentsmaychoosetouse.
Forthosewhochosevanilla:
P(vanilla)=7614/14766
P(vanilla|male)=3590/6010
BeginthewholegroupdiscussionaftermoststudentshavecompletedpartI.
Discuss(WholeClass):
Sequencestudentstosharetheirstrategiesfororganizingdata.Includeconnectionstheynotice
betweenrepresentations.Usemisconceptionsstudentsmayhavehadduringsmallgroupsto
Chocolate Vanilla Total
Female 4,732 4,024 8,756
Male 2,420 3,590 6,010
Total 7,152 7,614 14,766
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.2
Mathematics Vision Project
highlighthowtodeterminevalues.Foreachsituation,encouragestudentstouseappropriate
academiclanguage.
ExplorePartII(SmallGroups):
Havestudentscompletequestions5and6.Studentsshouldbeabletoarticulatehoweach
representationorganizesthedatatohighlightcertaininformation.Thegoalofthisportionofthe
taskisforstudentstobecomemorecomfortablewitheachrepresentationsotheycanchoose
whichrepresentationtouseinthefuturewhenorganizingdata.Ifstudentsseemstuck,askthemto
writeaprobabilitythatis‘easier’toseeinthetreediagramthanintheothertworepresentations.
Likewise,writeaprobabilitythatis‘easier’toseeinthetwowaytableorthatis‘easier’toseeinthe
VennDiagram.
DiscussPartII(WholeClass):
Completethechartasawholegroupafterstudentshavehadtimetothinkaboutthisthemselves.
Toconclude,answerquestionsixbydiscussingthelawoflargenumbersandrandomness.
AlignedReady,Set,Go:ProbabilityRSG9.2
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.2
Mathematics Vision Project
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9.2
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READY
Topic:AnalyzingdatagiveninaVennDiagram.
UsetheVennDiagramsbelowtoanswerthefollowingquestions.(Hint:youmayusethesamedataprovidedinthetwo-waytablefromquestion3onthenextpagetohelpmakesenseoftheVennDiagram)ThefollowingVennDiagramrepresentstherelationshipbetweenfavoritesport(SoccerorBaseball)andgender(FemaleorMale).
1.Howmanypeoplesaidsocceristheirfavoritesport?
2.Howmanyfemalesareinthedata?
3.Howmanymaleschosebaseball?
4.Whatistheprobabilitythatapersonwouldsaysocceristheir
favoritesport?P(soccer)=
5.Whatistheprobabilitythatafemalewouldsaysocceristheirfavoritesport?(“Outofallfemales,
____%saysocceristheirfavoritesport”)P(soccer|female)=
ThefollowingVennDiagramrepresentstherelationshipbetweenfavoritesubject(MathorScience)andgradelevel(NinthorTenth).Usingthisdata,answerthefollowingquestions.
6.Howmanypeoplesaidmathistheirfavoritesubject?
7.Howmanytenthgradersareinthedata?
8.Howmanyninthgraderschosescience?
9.Whatistheprobabilitythatapersonwouldsayscienceistheir
favoritesubject?P(s)=
10.Whatistheprobabilitythatatenthgraderwouldsayscienceistheirfavoritesubject?(“Ifyouarea
tenthgrader,thentheprobabilityofsciencebeingyourfavoritesubjectis_____%”)P(science|tenth)=
READY, SET, GO! Name PeriodDate
30
25
7
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.2
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SET Topic:Writingconditionalstatementsfromtwo-waytables
11.Completethetableandwritethreeconditionalstatements.
Soccer Baseball Total
Male 30
Female 50 76
Total 85
12.Completethetableaboutpreferredgenreofreadingandwritethreeconditionalstatements.
Fiction
Non-
Fiction
Total
Male 10
Female 50 60
Total 85
13.CompletethetableaboutfavoritecolorofM&M’sandwritethreeconditionalstatements.
Blue Green Red Other Total
Male 15 20 15 60
Female 30 20 10
Total 45 130
14.Usetheinformationprovidedtomakeatreediagram,atwo-waytableandaVennDiagram.
• Datawascollectedatthemovietheaterlastfall.Notaboutmoviesbutclothes.
• 6,525peoplewereobserved.
• 3,123hadonshortsandtheresthadonpants
• 45%ofthosewearingshortsweredenim.
• Ofthosewearingpants88%weredenim.
8
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.2
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GO Topic:BasicProbability
Findthedesiredvalues.
15.Whatishalfofone-third? 16.Whatisone-thirdoftwo-fifths?
17.Whatisone-fourthoffour-sevenths? 18.Whatpercentis!!?
19.Whatis35%of50? 20.Seventyis60%ofwhatnumber?
21.Write!!"asapercent. 22.Write
!!asapercent.
23.Whatis52%of1,200? 24.Whatpercentis32of160?
25.Sixtyiswhatpercentof250? 26.Whatpercentof350is50?
9
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.3
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
9.3 Fried Freddy’s A Solidify Understanding Task
Daniellewassurprisedbytheresultsofthesurveytodetermine
the‘favoriteicecream’betweenchocolateandvanilla(Seetask
9.2Chocolatevs.Vanilla).Thereason,sheexplains,isthatshehadaskedseveralofherfriends
andtheresultswereasfollows:
1. Inthissituation,chocolateismostpreferred.Howwouldyouexplaintoherthatthisdata
maybeless‘valid’comparedtothedatafromtheprevioussurvey?
Usingasufficientlylargenumberoftrialshelpsusestimatetheprobabilityofaneventhappening.If
thesampleislargeenough,wecansaythatwehaveanestimatedprobabilityoutcomeforthe
probabilityofaneventhappening.Ifthesampleisnotrandomlyselected(onlyaskingyourfriends)
ornotlargeenough(collectingfourdatapointsisnotenoughinformationtoestimatelongrun
probabilities),thenoneshouldnotestimatelargescaleprobabilities.Sometimes,oursample
increasesinsizeovertime.Belowisanexampleofdatathatiscollectedovertime,sotheestimated
probabilityoutcomebecomesmorepreciseasthesampleincreasesovertime.
Freddylovesfriedfood.Hispassionfortheperfectfriedfoodrecipesledtohimopeningthe
restaurant,“FriedFreddies.”Histwomaindishesarefocusedaroundfishorchicken.Knowinghe
alsohadtoopenuphismenutopeoplewhoprefertohavetheirfoodgrilledinsteadoffried,he
createdthefollowingmenuboard:
Chocolate Vanilla Total
Female 23 10 33
Male 6 8 14
Total 29 18 47
CCBYhttps://flic.kr/p/9a7kMg
10
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.3
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Afterbeingopenforsixmonths,Freddyrealizedhewashavingmorefoodwastethanheshould
becausehewasnotpredictinghowmuchofeachheshouldprepareinadvance.Hisbusinessfriend,
Tyrell,saidhecouldhelp.
2. WhatinformationdoyouthinkTyrellwouldneed?
Luckily,FreddyusesacomputertotakeorderseachdaysoTyrellhadlotsofdatatopullfrom.AfterdeterminingtheaveragenumberofcustomersFreddyserveseachday,TyrellcreatedthefollowingVenndiagramtoshowFreddythefoodpreferenceofhiscustomers:
Tomakesenseofthediagram,Freddycomputedthefollowingprobabilitystatements:
3. Whatistheprobabilitythatarandomlyselectedcustomerwouldorderfish?
P(fish)=
Shadethepartofthediagramthatmodelsthissolution.
30%15%20%
Fried Fish
Choose dish: Chicken or Fish
Choose cooking preference: Grilled or Fried
35%
11
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.3
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
4. Whatistheprobabilitythatarandomlyselectedcustomerwouldorderfried
fish?
P(fried∩fish)=P(friedandfish)=
Shadethepartofthediagramthatmodelsthissolution.
5. Whatistheprobabilitythatapersonprefersfriedchicken?
P(fried∩chicken)=P(friedandchicken)=
Shadethepartofthediagramthatmodelsthissolution.
6. Whatistheestimatedprobabilitythatarandomlyselectedcustomerwould
wanttheirfishgrilled?
P(grilledandfish)=P(____________________)=
Shadethepartofthediagramthatmodelsthissolution.
7. IfFreddyserves100mealsatlunchonaparticularday,howmanyordersoffishshouldhe
preparewithhisfamousfriedrecipe?
8. Whatistheprobabilitythatarandomlyselectedpersonwouldchoosefishor
fried?
P(fried∪fish)=P(friedorfish)=Shadethepartofthediagramthatmodelsthissolution.
9. WhatistheprobabilitythatarandomlyselectedpersonwouldNOTchoose
fishorfried?
Shadethepartofthediagramthatmodelsthissolution.
12
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.3
Mathematics Vision Project Licensed under the Creative Commons Attribution CC BY 4.0 mathematicsvisionproject.org
9.3 Fried Freddy’s – Teacher Notes A Solidify Understanding Task
Purpose:Apurposeofthistaskisforstudentstogainastrongerunderstandingthelawoflarge
numbersandhowthishelpstoestimateprobableoutcomes.Anotherpurposeisforstudentsto
solidifytheirunderstandingaroundthefollowingideas:
● Whetherornotthereisenoughdatatoestimateoutcomes.
● Distinguishbetweenageneralprobability,aconditionalprobability,andtheadditionrule.
● UseaVenndiagramtoanalyzedataandtowritevariousprobabilitystatements(unions,
intersections,complements).
● ApplytheAdditionRuleandinterprettheanswerintermsofthemodel.
● Useestimatedoutcomestomakerecommendationsanddecisions.
CoreStandardsFocus:
S.CP.1:Describeeventsassubsetsofasamplespace(thesetofoutcomes)usingcharacteristics(or
categories)oftheoutcomes,orasunions,intersections,orcomplementsofotherevents(“or”,
“and”,“not”).
S.CP.4:Constructandinterprettwo-wayfrequencytablesofdatawhentwocategoriesare
associatedwitheachobjectbeingclassified.Usethetwo-waytableasasamplespacetodecideif
eventsareindependentandtoapproximateconditionalprobabilities.
S.CP.6:FindtheconditionalprobabilityofAgivenBasthefractionofB’soutcomesthatalsobelong
toA,andinterprettheanswerintermsofthemodel.
S.CP.7:ApplytheAdditionRuleandinterprettheanswerintermsofthemodel.
RelatedStandards:S.CP.3,S.CP.5
TheTeachingCycle
Launch(WholeClass):
Havestudentsanswerthefirstquestionaboutthevalidityofdataindividually,thendiscussasa
grouphowimportantsampleiswhenestimatingoutcomes.
SECONDARY MATH II // MODULE 9
PROBABILITY- 9.3
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ReadthecontextofFriedFreddy,thenhavestudentsanswerthequestionaboutwhatinformation
Tyrellwouldneedtopulltogetherdata.Dependingonyourclass,youmayalsowishtohave
studentslabeleachsectionoftheVenndiagramandmakesureeveryoneunderstandsthispriorto
havingstudentsanswerthequestionsrelatedtothediagram.
Explore(SmallGroup):
Asyoumonitor,listenforstudentstomakesenseoftheprobabilitystatementstheyareanswering
andlookforthesolutionareatobeshadedontheirmodels.Helpstudentswhoarestrugglingby
suggestingtheycreateadifferentrepresentation(suchasatwo-waytable-seebelow).
Sincethepurposeofthistaskisforstudentstorecognizeanduseprobabilitystatementsto
interpretdata,plantohavethewholegroupdiscussionfocusonquestionsthatrelatetostandards
S.CP.1andS.CP.7.
Discuss(WholeClass):
ChoosestudentstoanswerquestionsrelatingtothedatafromtheVenndiagram.Spendmosttime
onquestionsrelatingtounions,intersections,complements,andtheAdditionRule.Besuretouse
thisvocabularyandhavestudent’srecordunfamiliarvocabularyintheirjournal.Themosttime
maybespentonquestionssixthroughnine.Attheendofthelesson,reviewprobabilitynotation
anddiscussthesimilaritiesanddifferencesbetweentherulesofprobability(unions,intersections,
complements,AdditionRule,conditionalprobability)andothervocabulary(mutuallyexclusive,
joint,disjoint).
AlignedReady,Set,Go:ProbabilityRSG9.3
Fish Chicken total
Fried 15% 20% 35%
Grilled 30% 35% 65%
Total 45% 55% 100%
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.3
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Topic:IndependentandDependentEventsInsomeofthesituationsdescribedbelowthefirsteventeffectsthesubsequentevent(dependentevents).Inotherseachoftheeventsiscompletelyindependentoftheothers(independentevents).Determinewhichsituationsaredependentandwhichareindependent.1. Acoinisflippedtwice.Thefirsteventisthefirstflipandthesecondeventisthenextflip.
2. Abagofmarblescontains3bluemarbles,6redmarblesand2yellowmarbles.Twoofthemarblesaredrawnoutofthebag.Thefirsteventisthefirstmarbletakenoutthesecondeventisthesecondmarbletakenout.
3. Anattempttofindtheprobabilityoftherebeingaright-handedoraleft-handedbatterattheplateinabaseballgame.Thefirsteventisthe1stbattertocometotheplate.Thesecondeventisthesecondplayertocomeuptotheplate.
4. Astandarddieisrolledtwice.Thefirsteventisthefirstrollandthesecondeventisthesecondroll.
5. Twocardsaredrawnfromastandarddeckofcards.Thefirsteventisthefirstcardthatisdrawnthesecondeventisthesecondcardthatisdrawn.
SET Topic:AdditionRule,InterpretingaVennDiagram6.SallywasassignedtocreateaVenndiagramtorepresent!(! or !).Sallyfirstwrites!(! or !) = !(!) + !(!) − !(! and !),whatdoesthismean?Explaineachpart.
7.Sallythencreatesthefollowingdiagram.
Sally’sVenndiagramisincorrect.Why?
READY, SET, GO! Name PeriodDate
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TheVenndiagramtotherightshowsthedatacollectedatasandwichshopforthelastsixmonthswithrespecttothetypeofbreadpeopleordered(sourdoughorwheat)andwhetherornottheygotcheeseontheirsandwich.Usethisdatatocreateatwo-wayfrequencytableandanswerthequestions.
8.Two-wayfrequencytable
9. Whatistheprobabilitythatarandomlyselectedcustomerwouldordersourdoughbread?
P(sourdoughbread)=10. Whatistheprobabilitythatarandomlyselectedcustomerwouldordersourdoughbreadwithout
cheese?P(sourdough∩nocheese)=P(sourdoughandnocheese)=
11. Whatistheprobabilitythatapersonpreferswheatbreadwithoutcheese?P(wheat∩nocheese)=P(wheatandnocheese)=
12. Whatistheestimatedprobabilitythatarandomlyselectedcustomerwouldwanttheirsandwichwithcheese?P(sourdoughcheeseandwheatcheese)=P(____________________)=
13. Iftheyserve100sandwichesatlunchonaparticularday,howmanyorderswithsourdoughshouldbepreparedwithoutcheese?
14. Whatistheprobabilitythatarandomlyselectedpersonwouldchoosesourdoughorwithoutcheese?P(sourdough∪nocheese)=P(sourdoughornocheese)=
15. WhatistheprobabilitythatarandomlyselectedpersonwouldNOTchoosesourdourghornocheese?
20%
14
SECONDARY MATH II // MODULE 9
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GO Topic:EquivalentRatiosandProportionsUsethegivenratiotosetupaproportionandfindthedesiredvalue.
16. If3outof5studentseatschoollunchthenhowmanystudentswouldbeexpectedtoeatschool
lunchataschoolwith750students?
17. Inawelldevelopedandcarriedoutsurveyitwasfoundthat4outof10studentshaveapairofsunglasses.Howmanystudentswouldyouexpecttohaveapairofsunglassesoutofagroupof45students?
18. Datacollectedatalocalmallindictedthat7outof20menobservedwerewearingahat.Howmanywouldyouexpecttohavebeenwearinghatsif7500menweretobeatthemallonasimilarday?
15
SECONDARY MATH II // MODULE 9
PROBABILITY-9.1
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9.4 Visualizing with Venn
A Solidify Understanding Task OneoftheattributesofVenndiagram’sisthatitcanbeeasytoseetherelationshipswithinthedata.Inthistask,wewillcreatemultipleVenndiagramsusingdataanddeterminetheeventsthatcreatediagramstoeitherhaveanintersectionorforthemtobemutuallyexclusive.1. ThefollowingdatarepresentsthenumberofmenandwomenpassengersaboardtheTitanicand
whetherornottheysurvived.Fillintheblanksforthistable:
Survived Didnotsurvive Total
Men 659 805
Women 296
Total 442 765 1207
2. Usingthedataabove,createaVenndiagramforeachofthefollowing:a. MenvsWomen b. WomenvsSurvivedc. Youchoosetheconditions
3. CreatetwoprobabilitystatementsusingeachofyourVenndiagramsfromquestion2.
4. CreateandlabelthreedifferentVenndiagramsusingthefollowingdata.Createatleastonethatismutuallyexclusiveandatleastonethathasanintersection.Samplesize:100
P(girl)= !"!""P(girlorart)=( !"!"" + !"!"") −
!"!""
P(art)= !"!""P(notart)=P(boy)=
5. DescribetheconditionsthatcreatemutuallyexclusiveVenndiagramsandthosethatcreateintersections.
6. WhatconjecturecanyoumakeregardingthebestwaytocreateaVenndiagramfromdatatohighlightprobabilities?
CC
BY
htt
ps://
flic.
kr/p
/9a7
kMg
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PROBABILITY-9.1
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9.4 Visualizing with Venn- Teacher Notes A Solidify Understanding Task
Purpose:ThepurposeofthistaskistohavestudentscreateandanalyzeattributesofVenndiagrams,
thenmakesenseofthedata.Studentswilladdacademicvocabulary(mutuallyexclusive,joint,disjoint)
andwilldistinguishbetweenconditionalprobabilityandusingtheadditionrule.Attheendofthetask,
studentswillbeableto:
● CreateVennDiagramsthathighlightspecificdata.
● Understandmutuallyexclusive,joint(intersection),andtheAdditionRuleusingVenn
diagrams.
● DistinguishbetweenconditionalprobabilityandtheAdditionRule.
● Getoutvocabularysuchasjoint,disjoint,mutuallyexclusive,AdditionRule,andconditional
probability.
● AnalyzingdatafromatwowaytableandfromprobabilitynotationtocreatevariousVenn
Diagrams
CoreStandardsFocus:S.CP.6:FindtheconditionalprobabilityofAgivenBasthefractionofB’soutcomesthatalsobelongto
A,andinterprettheanswerintermsofthemodel.
S.CP.7:ApplytheAdditionRule,P(AorB)=P(A)+P(B)–P(AandB),andinterprettheanswerinterms
ofthemodel.
RelatedStandards:S.CP.3,S.CP.4,S.CP.5
TheTeachingCycle:
Launch(WholeClass):
HavestudentssharewhattheyknowaboutVenndiagramstoaccessbackgroundknowledge,thenhave
thembeginworkingonthetaskinsmallgroups.
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Explore(SmallGroup):
Asyoumonitor,checkforstudentunderstandingofhowtowriteaVenndiagramwhengiventhe
constraints(questionstwoandthree).Thesequestionsscaffoldstudentsbytellingthemwhich
categoriestousewhencreatingthediagram,thenhavingtheminterpretwhatkindofinformationthey
canseefromeach.Theintentionofthesemodelsisforstudentstorecognizethatwhentheyare
choosingcategoriesforaVenndiagram,thatthedataismoremeaningfulwhentheyselectfrom
differentcategorytypes.ListenforstudentstomakethefollowingconjecturesregardingcreatingVenn
diagrams:Iftwoeventsarerelatedandhaveoverlappingdata,theintersectioniseasytoseeand
severalprobabilitystatementscanbemade.Likewise,ifthetwoeventsbeingcompareddonothave
overlap,thenthosetwoeventsaremutuallyexclusive.Alsolistenforstudentstobecomeclearastothe
probabilitiesthatareeasiertoseeinaVenndiagramthaninothermodels.
Discuss(WholeClass):
Vocabularytosolidifyduringdiscussionusingstudentwork:mutuallyexclusive,AdditionRule,
intersections,complements,disjoint,andjoint.
Forthewholegroupdiscussion,havestudentssharewhattheyhavelearnedaboutcreatingVenn
diagrams.Chartthisinformation,andthenpressstudentstoexplainhowtheywouldusedatainthe
futuretocreateaVenndiagramthatwouldproducethedatatheywereseeking.Askstudentstoshare
someprobabilitystatementstheycreatedandhavethemexplainhowtheVenndiagramwashelpfulin
seeingtheprobability.Focusonconditionalprobabilitystatements,theAdditionRule,anddatathat
highlightsintersectionsandcomplements.
AlignedReady,Set,Go:ProbabilityRSG9.4
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.4
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READY
Topic:Productsofprobabilities,multiplyinganddividingfractionsFindtheproductsorquotientsbelow.
1. 12 ∙23
2. 35 ∙13
3. 710 ∙
25
4. 87 ∙34
5. 1312
6. 25 ÷
23
7. P(A)=!!P(B)=
!!
P(A)∗P(B)=
8. P(A)=!!P(B)=!!
P(A)∗P(B)=
SET Topic:ConnectingrepresentationsofeventsforprobabilityForeachsituation,oneoftherepresentations(two-waytable,Venndiagram,treediagram,contextorprobabilitynotation)isprovided.Usetheprovidedinformationtocompletetheremainingrepresentations.9.AreyouBlue?
Notation 2-wayTableKey:Male=MFemale=FBlue=BNotBlue=NSamplesize=200P(B)=84/200P(M)=64/200P(F|B)=48/84P(B|F)=P(M∩B)=P(M∪B)=
Blue NotBlue
Total
Male
Female
Total
(Continuedonthenextpage)
READY, SET, GO! Name PeriodDate
17
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(Continued from the last page)
VennDiagram TreeDiagram
Writethreeobservationsyoucanmakeaboutthisdata.
10.Rightandlefthandednessofagroup.Notation 2-wayTable
Key:Male=MFemale=FLefty=LRighty=RSamplesize=100peopleP(L)=P(M)=P(F)=P(L|F)=P(L|M)=
Lefty Righty Total
Male
Female
Total
VennDiagram TreeDiagram
Writethreeconditionalstatementsregardingthisdata.
18
SECONDARY MATH II // MODULE 9
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11.Themostimportantmealoftheday.Notation 2-wayTable
Key:Male=MFemale=FEatsBreakfast=EDoesn’tEatBreakfast=DSamplesize=P(E)=P(E|M)=P(E∩M)=P(E|F)=P(E∩F)=
Eats Doesn’t Total
Male
Female
Total 685
VennDiagram TreeDiagram
Doesthisdatasurpriseyou?Whyorwhynot.
GO Topic:Writingconditionalstatementsfromtwo-waytables12.Completethetableandwritethreeconditionalstatements.
Biking Swimming TotalMale 50 Female 35 76Total 85
13.Completethetableaboutpreferredgenreofreadingandwritethreeconditionalstatements.
IceCream
Cake Total
Male 20 Female 10 60Total 85
14.Completethetableabouteyecolorandwritethreeconditionalstatements. Blue Green Brown Other Total
Male 55 20 15 100Female 20 10 Total 75 230
19
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.5
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9.5 Freddy Revisited A Solidify Understanding Task
Intask9.3FriedFreddy’s,TyrellhelpedFreddyin
determiningtheamountandtypeoffoodFreddyshouldprepareeachdayforhisrestaurant.Asa
result,Freddy’sfoodwastedecreaseddramatically.Astimewentby,Freddynoticedthatanother
factorheneededtoconsiderwasthedayoftheweek.Henoticedthathewasoverpreparingduring
theweekandsometimesunderpreparingontheweekend.TyrellandFreddyworkedtogetherand
startedcollectingdatatofindtheaveragenumberofordershereceivedofchickenandfishona
weekdayandcomparedittotheaveragenumberofordershereceivedofeachontheweekend.
Aftertwomonths,theyhadenoughinformationtocreatethetwowaytablebelow:
Fish Chicken TotalWeekday 65 79 144Weekend 88 107 195Total 153 186 339
1. Whatobservationscanbemadefromthetable(includeprobabilitystatements)?
2. Whatdoyounoticeabouttheprobabilitystatements?
3. Basedonthedata,ifFreddyhadasalespromotionandanticipated500ordersinagivenweek,howmanyofeach(chickenandfish)shouldheorder?
CcbyNicoleAbaldi
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PPOBABILITY- 9.5
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9.5 Freddy Revisited – Teacher Notes A Solidify Understanding Task
Purpose:Thepurposeofthistaskisforstudentstodetermineiftwoeventsareindependent.In
thistask,studentsareaskedtointerprettheamountoffishandchickenFreddyshouldprepareon
anygivenday.ThegoalisforstudentstorecognizethatFreddysellsmorefoodonaweekendday
thanhedoesonaweekday,however,thepercentageofeachfoodtypestaysthesame.Inother
words,thelikelihoodthatarandomlyselectedcustomerwouldorderchickenisindependentasto
whetherornotitisaweekdayoraweekend.
CoreStandardsFocus:
S.CP.2:UnderstandthattwoeventsAandBareindependentiftheprobabilityofAandBoccurring
togetheristheproductoftheirprobabilities,andusethischaracterizationtodetermineiftheyare
independent.
S.CP.3:UnderstandtheconditionalprobabilityofAgivenBasP(AandB)/P(B),andinterpret
independenceofAandBassayingthattheconditionalprobabilityofAgivenBisthesameasthe
probabilityofA,andtheconditionalprobabilityofBgivenAisthesameasthe
probabilityofB.
S.CP.4:Constructandinterprettwo-wayfrequencytablesofdatawhentwocategoriesare
associatedwitheachobjectbeingclassified.Usethetwo-waytableasasamplespacetodecideif
eventsareindependentandtoapproximateconditionalprobabilities.Forexample,collect
datafromarandomsampleofstudentsinyourschoolontheirfavoritesubjectamongmath,science,
andEnglish.Estimatetheprobabilitythatarandomlyselectedstudentfromyourschoolwillfavor
sciencegiventhatthestudentisintenthgrade.Dothesameforothersubjectsandcomparethe
results.
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.5
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S.CP.5:Recognizeandexplaintheconceptsofconditionalprobabilityandindependencein
everydaylanguageandeverydaysituations.Forexample,comparethechanceofhavinglungcancer
ifyouareasmokerwiththechanceofbeingasmokerifyouhavelungcancer.
RelatedStandards:S.CP.6,S.MD.7+
TheTeachingCycle:
Launch(WholeClass):
BeginwithremindingstudentsaboutthetaskFriedFreddy’sandhowTyrellhelpedFreddy
determinetheamountofchickenandfishheshouldprepareeachday.Launchintothistaskby
sharingthescenario,thenhavestudentsanswerthethreequestions.
Explore(SmallGroup):
Insmallgroups,havestudentsmakeasmanyobservationsaspossibleastotheamountoffood
Freddyshouldprepare.Someobservationsmaybesimple(suchas‘Freddyservesmorechicken
thanfish’),butotherobservationsmayincludethefollowing:
• Additiveobservation:Freddyservesmorechickenthanfish:thereare14moreorders
ofchickenthanfisheachweekday.
• Probabilitystatement(multiplicativeobservation):Giventhatitisaweekday,55%of
Freddy’sbusinessordersarechicken.
• Probabilitystatement(multiplicativeobservation):Giventhatitisaweekend,55%of
Freddy’sbusinessordersarechicken.
• Probabilitystatement(multiplicativeobservation):55%ofFreddy’sbusinessordersare
chicken(regardlessofwhetheritisaweekdayorweekend).
• Additive:Thereare23moreordersoffishontheweekendthanduringtheweek.
• Additive:Thereare28moreordersofchickenontheweekendthanduringtheweek.
• Additive:Thereare51moreordersontheweekendthanduringtheweek.
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.5
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• Multiplicative:Thereisa35.4%increaseinthenumberofordersforfishonthe
weekendthanduringtheweek.
• Multiplicative:Thereisa35.4%increaseinthenumberofordersforchickenonthe
weekendthanduringtheweek.
• Multiplicative:Thereisa35.4%increaseinthenumberofordersforfoodonthe
weekendthanduringtheweek.
• Probabilitystatement(multiplicativeobservation):45%ofFreddy’sbusinessorders
fish,regardlessofwhetherornotitisaweekdayoraweekend.
Therearemanyobservationsstudentscanmakeatthispoint.Thegoalistodistinguish
observationsthatareprobabilitystatementsversus‘additive’observations.
Discuss(WholeClass):
Beginthediscussionphasebyhavingstudentsshareobservationsingeneral,thenhoneinonthe
probabilitystatements.Selectastudenttosharewhohasnoticedthattheconditionalprobabilityis
thesameasageneralprobabilitystatement.Atthispoint,introducethevocabularyofindependent
eventsandexplainthattwoeventsareconsideredindependentwhentheconditionalprobabilityof
AgivenBisthesameastheprobabilityofA.Next,showtheconditionalprobabilitytestfor
independenceusingnotation(forexample:P(fish|weekday)=f(fish)).Askstudentstoconsiderthe
examplejustsharedandtodetermineiftheexampleshowstwoindependentevents.Havestudents
sharewiththeirpartnerandexplainwhytheeventsareindependentornot.
Haveanotherstudentshareadifferentobservationusingaprobabilitystatement,andthenaskthe
classtofindoutiftheseareindependentevents.Attheendofthistask,allstudentsshouldbeable
torecognizethatfishisindependentfromthedayoftheweekbecausethepercentofpeoplewho
preferfish,giventhatitisaweekday(orweekend)isthesameasthepercentofpeoplewhoprefer
fishingeneral.
Usenotationtoshowthisrelationship.Dothesamewithchickengiventhatitisaweekday.Show
thisdatausingatreediagramandaVenndiagram.Whatdostudentsnoticeregardingindependen
cewhendataispresentedinaparticularrepresentation?Again,usenotationtoshowindependence
andthenconnectthistoeachrepresentationyouhavedrawn.Concludethetaskbywriting
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.5
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independencestatements,drawingarepresentationmodelthatmatchesandconnectingto
standardsS.CP.2,S.CP.3,S.CP.4,andS.CP.5.
AlignedReady,Set,Go:ProbabilityRSG9.5
SECONDARY MATH II // MODULE 9
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Topic:QuadraticfunctionsFindthex-intercepts,y-intercept,lineofsymmetryandvertexforthequadraticfunctions.
1.!(!) = !! + 8!– 9
2.! ! = !!– 3! – 5 3.ℎ ! = 2!! + 5! − 3
4.!(!) = !! + 6! – 9 5.!(!) = (! + 5)!– 2 6.!(!) = (! + 7)(! – 5)
SET Topic:IndependenceDeterminingtheindependenceofeventscansometimesbedonebybecomingfamiliarwiththecontextinwhichtheeventsoccurandthenatureoftheevents.Therearealsosomewaysofdeterminingindependenceofeventsbasedonequivalentprobabilities.
• Twoevents,AandB,areindependentifP(AandB)=P(A)∙P(B)• Additionally,twoevents,AandB,areindependentifP(A|B)=!(! !"# !)
!(!) =P(A)
Usethesetwowaysofdeterminingindependenteventstodetermineindependenceintheproblemsbelowandanswerthequestions.
7.P(AandB)=!!
P(A)=!!P(B)= !!"
8.P(A)=!!
P(AandB)=!!
P(B)=!!
9.P(A)=!!
P(AandB)=!!
P(B)=!!
10.P(AandB)=!!
P(A)=!!P(B)=!!
READY, SET, GO! Name PeriodDate
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GO Topic:FindProbabilitiesfromatwo-waytableThefollowingdatarepresentsthenumberofmenandwomenpassengersaboardthetitanicandwhetherornottheysurvived.
Survived Didnotsurvive Total
Men 146 659 805
Women 296 106 402
Total 442 765 1207
11. P(w)=
12. P(s)=
13. P(s|w)=
14. P(wors)=
15. P(worm)=
16. P(ns|w)=
17. P(m∩ns)=
22
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.6
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9.6 Striving for Independence A Practice Understanding Task
Answerthequestionsbelowusingyourknowledgeofconditional
probability(theprobabilityofAgivenBasP(AandB)/P(B))as
wellasthedefinitionofindependence.Twoevents(AandB)aresaidtobeindependentif
! !|! = ! ! !"# ! !|! = !(!).Keeptrackofhowyouaredeterminingindependenceforeachtypeofrepresentation.
1. Outofthe2000studentswhoattendacertainhighschool,1400studentsowncellphones,
1000ownatablet,and800haveboth.CreateaVenndiagrammodelforthissituation.Use
properprobabilitynotationasyouanswerthequestionsbelow.
a) Whatistheprobabilitythatarandomlyselectedstudentownsacellphone?
b) Whatistheprobabilitythatarandomlyselectedstudentsownsbothacellphoneanda
tablet?
c) Ifarandomlyselectedstudentownsacellphone,whatistheprobabilitythatthis
studentalsoownsatablet?
d) Howarequestionsbandcdifferent?
e) Aretheoutcomes,ownsacellphoneandownsatablet,independent?Explain.
2. BelowisapartiallycompletedtreediagramfromthetaskChocolatevsVanilla.
a) Circlethepartsofthediagramthatwouldbeusedtodetermineifchoosingchocolateis
independentofbeingamaleorfemale.
b) Completethediagramsothatchoosingchocolateisindependentofbeingmaleorfemale.
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23
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.6
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3. UsethedatafromtheTitanticbelowtoanswerthefollowingquestions.
Survived Didnotsurvive TotalMen 146 659 805Women 296 106 402Total 442 765 1207
a) Determineifsurvivalisindependentofbeingmaleforthisdata.Explainorshowwhyor
whynot.Ifitisnotindependentdeterminehowmanymenwouldneedtosurvivein
ordertomakeitindependent.
4. Determinewhetherthesecondscenariowouldbedependentorindependentofthefirst
scenario.Explain.
a) Rollingasix-sideddie,thendrawingacardfromadeckof52cards.
b) Drawingacardfromadeckof52cards,thendrawinganothercardfromthesamedeck.
c) Rollingasix-sideddie,thenrollingitagain.
d) Pullingamarbleoutofabag,replacingit,thenpullingamarbleoutofthesamebag.
e) Having20treatsinfivedifferentflavorsforasoccerteam,witheachplayertakinga
treat.
24
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.6
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9.6 Striving for Independence – Teacher Notes A Practice Understanding Task
Purpose:Thepurposeofthistaskisforstudentstopracticedeterminingwhetheroneeventis
independentofanotherevent.Studentswillusedatafromdifferentrepresentations,plusmake
senseofwhetherornotonescenariowouldbeindependentofanother.Intheend,studentswill
explainhowtoquicklydetermineindependencefromaVenndiagram,atreediagram,andatwo-
waytable.
CoreStandardsFocus:
S.CP.2:UnderstandthattwoeventsAandBareindependentiftheprobabilityofAandBoccurring
togetheristheproductoftheirprobabilities,andusethischaracterizationtodetermineiftheyare
independent.
S.CP.3UnderstandtheconditionalprobabilityofAgivenBasP(AandB)/P(B),andinterpret
independenceofAandBassayingthattheconditionalprobabilityofAgivenBisthesameasthe
probabilityofA,andtheconditionalprobabilityofBgivenAisthesameasthe
probabilityofB.
S.CP.4Constructandinterprettwo-wayfrequencytablesofdatawhentwocategoriesare
associatedwitheachobjectbeingclassified.Usethetwo-waytableasasamplespacetodecideif
eventsareindependentandtoapproximateconditionalprobabilities.Forexample,collect
datafromarandomsampleofstudentsinyourschoolontheirfavoritesubjectamongmath,science,
andEnglish.Estimatetheprobabilitythatarandomlyselectedstudentfromyourschoolwillfavor
sciencegiventhatthestudentisintenthgrade.Dothesameforothersubjectsand
comparetheresults.
S.CP.5Recognizeandexplaintheconceptsofconditionalprobabilityandindependenceineveryday
languageandeverydaysituations.Forexample,comparethechanceofhavinglungcancerifyouare
asmokerwiththechanceofbeingasmokerifyouhavelungcancer.
SECONDARY MATH II // MODULE 9
PPOBABILITY- 9.6
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S.CP.6:FindtheconditionalprobabilityofAgivenBasthefractionofB’soutcomesthatalsobelong
toA,andinterprettheanswerintermsofthemodel.
RelatedStandards:S.CP.1,S.CP.7
TheTeachingCycle:
Launch(WholeClass):
Startthistaskbyreviewingthedefinitionofindependence,thenhavestudentsworkinpairsto
practiceusingprobabilityanddeterminingiftwoeventsareindependentusingdatafromdifferent
representations.
Explore(SmallGroup):
Asyoumonitor,lookforstudentstousetheirknowledgeofconditionalprobabilityandtheformula
forindependencetodeterminewhethertwoeventsareindependentforeachsituation.Select
studentstosharehowtherepresentationandnotationareconnected,andexplainwhetherthetwo
eventsareindependent.
Discuss(WholeClass):
Thegoalofthewholegroupdiscussionisforstudentstobeabletofluentlywriteconditional
probabilitystatements,tomakesenseofconditionalprobabilityusingthedifferentrepresentations
theyhavebeenusingthroughoutthismodule,andtodetermineiftwoeventsareindependent.
Usingthegroupsyouselectedduringtheexplorephase,sequencetheorderofhowtheysharetheir
problemtoreachthegoalsofthetask.Foreachsituation,connecttherepresentationbeingusedto
theformulaforindependence.
AlignedReady,Set,Go:ProbabilityRSG9.6
SECONDARY MATH II // MODULE 9
PROBABILITY – 9.6
Mathematics Vision Project
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9.6
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READY
Topic:SolvingquadraticsSolveeachofthequadraticsbelowusinganappropriatemethod.
1.m2+15m+56=0 2.5x2–3x+7=0
3.x2−10x+21=0 4.6x2+7x–5=0
SET Topic:RepresentingIndependentEventsinVennDiagramsIneachoftheVennDiagramsthenumberofoutcomesforeacheventaregiven,usetheprovidedinformationtodeterminetheconditionalprobabilitiesorindependence.ThenumbersintheVennDiagramindicatethenumberofoutcomesinthatpartofthesamplespace.5.
a.Howmanytotaloutcomesarepossible?b.P(A)=c.P(B)=d.P(A∩B)=e.P(A|B)=
f.AreeventsAandBindependentevents?Whyorwhynot?
READY, SET, GO! Name PeriodDate
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SECONDARY MATH II // MODULE 9
PROBABILITY – 9.6
Mathematics Vision Project
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9.6
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6.
a.Howmanytotaloutcomesarepossible?b.P(E)=c.P(F)=d.P(E∩F)=e.P(E|F)=
f.AreeventsEandFindependentevents?Whyorwhynot?7.
a.Howmanytotaloutcomesarepossible?b.P(X)=c.P(Y)=d.P(X∩Y)=e.P(X|Y)=
f.AreeventsXandYindependentevents?Whyorwhynot?8.
a.Howmanytotaloutcomesarepossible?b.P(K)=c.P(L)=d.P(K∩L)=e.P(K|L)=
f.AreeventsKandLindependentevents?Whyorwhynot?
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SECONDARY MATH II // MODULE 9
PROBABILITY – 9.6
Mathematics Vision Project
Licensed under the Creative Commons Attribution CC BY 4.0
mathematicsvisionproject.org
9.6
Needhelp?Visitwww.rsgsupport.org
GO Topic:ConditionalProbabilityandIndependenceDatagatheredontheshoppingpatternsduringthemonthsofAprilandMayofhighschoolstudentsfromPeanutVillagerevealedthefollowing.38%ofstudentspurchasedanewpairofshorts(callthiseventH),15%ofstudentspurchasedanewpairofsunglasses(callthiseventG)and6%ofstudentspurchasedbothapairofshortandapairofsunglasses.9.Findtheprobabilitythatastudentpurchasedapairofsunglassesgiventhatyouknowtheypurchasedapairofshorts.P(G|H)=10.Findtheprobabilitythatastudentpurchasedapairofshortsorpurchasedanewpairofsunglasses.P(H∪G)=11.Giventheconditionthatyouknowastudenthaspurchasedatleastoneoftheitems.Whatistheprobabilitythattheypurchasedonlyoneoftheitems?12.ArethetwoeventsHandGindependentofoneanother?WhyorWhynot?Giventhedatacollectedfrom200individualsconcerningwhetherornottoextendthelengthoftheschoolyearinthetablebelowanswerthequestions.
For Against NoOpinion Youth(5to19) 7 35 12 Adults(20to55) 30 27 20 Seniors(55+) 25 16 28
20013.Giventhatconditionthatapersonisanadultwhatistheprobabilitythattheyareinfavorofextendingtheschoolyear?P(For|Adult)=14.GiventheconditionthatapersonisagainstextendingtheschoolyearwhatistheprobabilitytheyareaSenior?P(Senior|Against)=15.Whatistheprobabilitythatapersonhasnoopiniongiventhattheyareayouth?P(noopinion|youth)=
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