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2 Findthemeanofeachsetofdata.
a) 2,5,8,4,11
b) 0,3,9,2,2,11,15,32,7
c) 2,8,5,12,4
d) 17,24,15,42,63,71,7
3 Findthemedianofeachsetofdata.
a) 2,4,5,8,11
b) 2,5,8,4,11
c) 0,11,3,5,2,19
d) 44,40,41,49
e) 17,9,35,3,0,42
Understandanduse the mean,medianandmode
1 Herearefivetowersofcubes.
a) Whatisthemostcommonnumberofcubesusedinatower?
Whichaverageisthis?Circleyouranswer.
mode� median� mean
b) Thetowersareinascendingorderofheight.
Howmanycubesareinthemiddletower?
Whichaverageisthis?Circleyouranswer.
mode� median� mean
c) Thecubesareredistributedsothatthefivetowersarenowallthe
sameheight.
Howmanycubesareineachtowernow?
Whichaverageisthis?Circleyouranswer.
mode� median� mean
d) Completethesentences.
Themediannumberofcubesusedis
Themodalnumberofcubesusedis
Themeannumberofcubesusedis
©WhiteRoseMaths2020
A supporting video can be found at https://vimeo.com/432450580
6 Sixnumbershaveamodeof19,ameanof12andamedianof14
a) Fillinthecardstoshowwhatthenumberscouldbe.
b) Whatistherangeofyoursetofnumbers?
Compareyourrangewithapartner’s.
7 Themeanofthissetofdatais10.5
z+1 0 21 13 21 z 7 8
a) Workoutthevalueofz.
z=
b) Workoutthemedian,modeandrangeofthedata.
median mode range
c) Aninthcardisadded.
Themeanisnow12
Whatisthevalueoftheninthcard?
8 Writeanexpressionforthemeanofthecards.
3x 5x 7x 9x 2x 13x
4 Findthemodeofeachsetofdata.
a) 3,5,1,3,2,9,3
b) 17,11,9,9,17,6,9
c) 26.3,14.1,15.8,14.1,26.3,19.7,20.6
d) 0,1,2,3,4,5,6,7
e) red,blue,red,orange,yellow,green,yellow,blue,red,red,white
5 Themeanofthissetofdatais13
047112135
Doraisworkingoutthemeanofadifferentsetofdata.
158122236
ShowthatDoraiscorrect.
©WhiteRoseMaths2020
I don’t need to do any calculations. I know
that the mean is 14
2 Thetableshowsthenumberoflettersinthefirst100wordsinanew
children’sbook.
Numberofletters Numberofwords
1 11
2 15
3 22
4 17
5 12
6 11
7 9
8 3
a) Circlethemodalnumberoflettersinaword.
8 22 3 4
Foreachoftheanswersyouhavenotcircled,discusswithapartner
whysomebodymightthinktheyarethemode.
b) Circletherangeofthenumberoflettersinaword.
7 8 19 21
Foreachoftheanswersyouhavenotcircled,discusswithapartner
whysomebodymightthinktheyaretherange.
c) Evaisworkingoutthemeanofthedatainthetable.
HowcanyoutellstraightawaythatEvaisincorrect?
d) Workoutthemeanofthedatainthetable.
Find themean from an ungroupedfrequency table
1 Thedatashowstheagesof40peopleatanexerciseclass.
1 7 1 7 1 7 1 7 1 7 1 7 1 7
1 8 1 8 1 8 1 8 1 8
19 19 19 19 19 19 19 19 19
20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20
Annie,AmirandDexterareworkingoutthemeanofthedatausing
differentmethods.
Annie'smethod Addallthenumbersupanddividebyhow
manythereare.
Amir'smethod Workout7×17+5×18+9×19+19×20
andthendividebyhowmanynumbersthereare.
Dexter'smethod Useatable.
Age Frequency
17 7
18 5
19 9
20 19
Chooseonemethodtoworkoutthemean.
Whydidyouchoosethismethod?
Talkaboutitwithapartner.
©WhiteRoseMaths2020
H
1 1 + 1 5 + 2 2 + 1 7 + 1 2 + 1 1 + 9 + 3 = 1 0 01008
= 1 2 . 5
A supporting video can be found at https://vimeo.com/432450753
5 Ateacherasksanumberofstudentssixspellingquestions.
Thetableshowstheresults.
Numberofcorrectspellings 0 1 2 3 4 5 6
Numberofstudents 1 6 8 11 6 4
Theteachercalculatesthatthemeannumberofcorrectspellingswas3.4
Findthemissingdatainthetable.
6 ThreeYear9classessitamentalarithmetictest.
Thetableshowsthenumberofstudentsineachclassandthemean
numberofquestionseachclassgetscorrect.
ClassNumberof
students
Meannumberof
correctanswers
9A 32 23
9B 25 18
9C 20 15
Workouttheoverallmeanforallthestudents.
3 Thetableshowsthenumberofbedroomsin1,000housesinatown.
Thetableisincomplete.
Numberofbedrooms 1 2 3 4 5 6
Numberofhouses 33 124 237 380 186
a) Howmanyhouseshavesixbedrooms?
b) Statethemodalnumberofbedrooms.
c) Findthemeannumberofbedroomsperhouse.
4 Rosieplaysforalocalfootballteam.
Thefrequencydiagramshowshowmanygoalstheteamscoredinitsfirst
twentygames.
a) Findthenumberofgoalsscoredintotalinthetwentygames.
b) Findthemeannumberofgoalsscoredpergame.
©WhiteRoseMaths2020
0 1 2 3 40
1
2
3
4
6
5
7
8
numberofgoalsscoredingame
nu
mb
ero
fg
am
es
3 ThetableshowsMrGlover’smonthlyphonebillsovertwoyears.
Completethetable.
Phonebill,x(£) Frequency Midpoint frequency×midpoint
0≤x<10 7 5 7×5=35
10≤x<20 9 15 9×15=
20≤x<30 5
30≤x<40 3
Completethecalculationtofindanestimateofthemeanofhisphonebills.
estimateofmean≈totalcost
totalfrequency= =
4 Thetableshowsinformationabouttheamountoftimeagroupof
studentsspentonlineoneevening.
Completethetable.
Timeonline,
h(hours)Frequency Midpoint frequency×midpoint
0≤h<1 2 0.5
1≤h<2 12
2≤h<3 7
3≤h<4 5
4≤h<6 4
Completethecalculationtofindanestimateofthemeantimespentonline.
estimateofmean≈totaltime
totalfrequency= =
Find themean from agroupedfrequency table
1 Whatnumberisatthemidpointofeachnumberline?
a)
0 10
d)
11 20
b)
1 5
e)
20 30
c)
10 20
f)
41 50
2 Writethemidpointsoftheclassintervals.
a) 0≤x<10 c) 10≤x<20 e) 20≤x<40
b) 1≤x<10 d) 11≤x<20 f) 21≤x<40
©WhiteRoseMaths2020
H
A supporting video can be found at https://vimeo.com/432450874
7 Thetableshowstheamountoftimepeopletooktogetoutof
anescaperoom.
Time,t(minutes) Frequency Midpoint
0<t≤15 3
22.5 225
595
12 45
50<t≤60 1,100
a) Fillinanymissinginformationinthetable.
b) Writethemodalclassofthetimetaken.
c) Workoutanestimateforthemeantimetaken.
d)
DoyouagreewithMo?
Explainyouranswer.
5 Thetableshowssomeinformationaboutthemassesof30pets.
Mass,m(kg) Frequency
0≤m<2 8
2≤m<5 4
5≤m<10 12
10≤m<15 5
15≤m<25 1
a) Workoutanestimateforthemeanmassofthepets.
b) Writethemodalclassofthemasses.
6 Thetableshowssomeinformationaboutthewaitingtimesatapostoffice
onelunchtime.
Waitingtime,t(minutes) 0≤t<3 3≤t<4 4≤t<5 5≤t<10
Frequency 20 15 8 2
Workoutanestimateforthemeanwaitingtime.
©WhiteRoseMaths2020
I think the intervals should be 0 ≤ t < 15 not
0 < t ≤ 15, so the answer will be wrong.
2 Tommycomestoschooleitherbybusorbycar.
Hecompareshistraveltimes(inminutes)bybusandbycar.
Mean Range
Bus 16 7
Car 12 18
a) Onaverage,whichmethodoftransportisfaster?
Howdoyouknow?
b) Whichmethodoftransporthastheleastconsistentjourneytimes?
Howdoyouknow?
3 FilipandBrettaretrainingfora200msprint.
Thetimes(inseconds)fortheirpracticerunsareshown.
Filip 27 25 26 25 29 26 25 27 25
Brett 25 24 31 32 29 29 27 30 30
a) Whohasthefastestpracticeruntime?
b) Workoutthemedianpracticeruntimeforeachstudent.
Filip Brett
c) Workouttherangeofpracticeruntimesforeachstudent.
Filip Brett
d) Whohasthebestmedianrunningtime?
e) Whoisthemostconsistent?
Comparedistributionsusing averagesand the range
1 Aclasshasaspellingtesteveryweek.
Herearetheresultsoffourstudentsoverasix-weekperiod.
Teddy 688948 Esther 267899
Rosie 777777 Scott 867876
a) Workoutthemeanresultofeachstudent.
Teddy Rosie Esther Scott
b) Workouttherangeofresultsforeachstudent.
Teddy Rosie Esther Scott
c) Whichstudenthadthegreatestmean?
d) Whichstudentwasthemostconsistent?
e) Whodoyouthinkrevisedforthetests?
©WhiteRoseMaths2020
A supporting video can be found at https://vimeo.com/432451003
6 ThetableshowsthescoresofagroupofstudentsinEnglishand
Sciencetests.
English 47 36 72 42 51 78 38 47 38 52
Science 58 67 74 59 68 66 68 59 63 24
a) Completethetable.
Mean Median Range
Englishmarks
Sciencemarks
b) Useanaverageandtherangetomaketwocomparisonsbetweenthe
EnglishandSciencemarks.
1.
2.
7 Atacharity10,000mrace,twentyexperiencedrunnersfinishwith
ameantimeof48minutesandarangeof10minutes.
Herearethetimes(inminutes)oftenfirst-timerunnersintherace.
62 70 58 75 66 57 59 98 72 61
Maketwocomparisonsbetweentheexperiencedandfirst-timerunners.
1.
2.
Willyourcomparisonschangeiftherunnerwhotook98minutesisnot
includedinthedata?
4 Aboys’rugbyteamplayssevengames.
Hereisthenumberofpointstheyscoreineachgame.
14 31 12 27 22 45 16
a) Findthemedianofthenumberofpointsscored.
b) Findtherangeofthenumberofpointsscored.
Agirls’rugbyteamalsoplayssevengames.
Theirmedianscoreis28pointsandtherangeoftheirscoresis44points.
c) Usethemedianandrangetocomparetheperformancesoftheboys’
rugbyteamandthegirls’rugbyteam.
Median:
Range:
5 ForanEnglishassignment,Nijahiscomparingthenumberofwordsin
thirtysentencesoftwodifferentauthors.
Numberofwordsin
shortestsentence
Numberofwordsin
longestsentence
Mediannumberof
wordspersentence
AuthorA 6 15 10
AuthorB 10 23 14
a) Workouttherangeofthenumberofwordspersentencefor
eachauthor.
authorA authorB
b) Maketwocomparisonsaboutthenumberofwordspersentence
writtenbytheauthors.
1.�
2.� ©WhiteRoseMaths2020