-.$ @_. t:l

Determine the mean of the sampling distribution of p.

Q"a3lfrl: i I il{()urrd to ihlrr iii:'-in:alpla;cs as nucdr:.i.!p-

Determine the standard deviation of the sampling distribution of p.

The shape of the samplingdistribution of p is approximately normal becau

np(1 - p) > 10. (wcr]fo,,^ai) 2 l0 ^ 7t1z tcl ,,/ -#

#ir.$:f the sampling distribution of p is not normal because n < 0.05N *1Ur)

LO"^*f- *SttYJO

The shape of the sampling distribution of fr is not normal because n < 0.05N andnp(l-p) < ro. l1cct 9l'Abc/The shape of the sampling distribution of i is approximately normal because n < 0.05N urd

Vnp(t -p) < 10.

Je chm E,A

fr" ="r

llr=?

Student:Date:

Insfructor: Tosha Lamar Assignment: chp 8 examplesCourse: Fundamentals of Statistics (l)Book Sullivan: Fundamentals of Statistics,4e

Describe the sampling distribution of p. Assume the size of the population is 25,000.

n : 1000, p: 0.231

Describe the shape of the sampling distribution of fr. Choose the correct answer below.

Time:

t1.

, ,U.

, t-f

(r,"81*z)

a3i [i c }3Da

pao

--,T,oacl11ffiqv-

- C"ol*25 t '?,

Page 13

Student:Date:

lnstructor: Tosha Lamar- Assignment: chp 8 examplesCourse: pgadamentals of Statistics (l)Book Sullivan: Fundamentals of Statistics,4e

According to a sfudy conducted by a statistical organaation, the proportion of Americans who aresatisfied with the way things are going in their lives is 0.88. Suppose that a random sample of 100Americans is obtained. Complete parts (a) through (c). p = 61 88 ft : tfp(a) Describe the sampling distribution of i. Choos. th. .olo..t answer below.

t- .'t" Distribution of i is approximately normal 'th p;: 0.88 and o^ : 0.064992.

Time:

*

II

.l

T

a, acpS b

(Ittrrinir iri fi>iir rreri,riir pra;ts.';;;ia{crifr6

laaiat,a;n)c,ttri a,aJL'

7,,r\/'f,

Vn_-1- -^\a,ffiU-4.7\)

Laa

=\- c,a32+qbl53h

Student:Date:

Instructor: Tosha Lamar Assignment: chp 8 examples

Course: Fundnmentals of Statistics (l)Book Sullivan: Fundamentals of Statistics,4e

According to a survey in a country,36yo pf adults do not have any credit cards. Suppose a simplerandom sample of 300 adults is obtained. \-\ ft:: f ' 7t'.,random sample of 300 adults is obtained.

Y\'= 3x) > f= u,1@(a) Describe the sampling distribution of p, the sample proportion of adults who do not have a credit

card. Choose the phrase that best describes the shape of the sanpling distribution of f below.

rl * a,atrs( Tr\' Not normal because n < 0.05N and np(l - p) > 10.

P Notnormalbecausen<0.05Nandnp(l -p)<10. ^ /l -\--rlptt-t"-^l

Time:

ffi,:HI.il"}: ffi* ". l llX ;: ff -l] = il ?c(0, 3o)(( - c' &o)=

Q'1,t2Determine the mean of the sampling distribution of p. /

p^: : i*i,r'iri ,, ",,,

-,-:"' ,;,:", ff- ;: ,? 'c1t t Z Z tc v'

n_

[,rbi n €x^ =,WVe -Jv ^ €\rr :: 1i.:--Determine the standard deviation of the sampling distribution of p. Lr'i iJ6^: : ilii',rril,-i tr.; iitrer.: dr-rcir:.iitii:ia,.:,;s irs;i*cr,lcrl.! CY,.r ;

'' t:''Zl'!|" 0'\, e,tto(1"

,, pr'#.hE "r- ",,r, -"lts,whatistheprobabilitythat,;flr, *y**:: *#r,r?r?tKZq_:

' ,I)-.---.1 ... r'...--. ! .:-.-^t -1.. - I ! VThe probability is i i. iR+iurrlfr i'*rii rl.,;uir':i:l illaccs;rs ner.,Jrd

(c)WouldYtbeunusual,ifarandom5ampleof300adultsresultsTW"ingno,,,lutflfiZ77iZ8)

result is not unusual because the probability that p is greater than or equal to this sampleproportion is greater bhan 5Yo.

The result is not unusual because the probability that p is greater than or equal to this sampleproportion is less than SYo.

The result is unusual because the probability that fr is greater than or equal to this sampleproportion is less than 5Yo.

The result is unusual because the probability that i is greater than or equal to this sampleproportion is greater than 5Yo.

,,;Ft; J o,rq nunttri(tt( (i'n'l) )c'4qq)uilrc,D?l7l?$

rI} : c,l3q5

0,l%t 5 > C,c5

:r -:'-

-\,0,'11(1'c'$)'- \, <--'-

..1' .y't14

- \ ,' 0C'C833

: 0 "a2Kbl

Instructor: Tosha Lamar Assignment: chp 8 examplesCourse: Fundamentals of Statistics (l)Book Sullivan: Fundamentals of Statistics,4e

Exit polling is a popular technique used to determine the outcome of an election prior to results beingtallied. Suppose a referendum to increase funding for education is on the ballot in a large town (votingpopulation over 100,000).An exit poll of 300 voters finds that 153 voted for the referendum. Howlikely are the results of your sample if the population proportion of voters in the town in favor of the

The result is not unusual because the probability that p is equal to or more extreme than thesample proportion is less than 5oZ. Thus, it is unusual for a wrong call to be made in an electionif exit polling alone is considered.

The result is unusual because the probability thati is equul to or more extreme than the sampleproportion is greater that 5Yr. Thus, it is not rmusual for a wrong call to be made in an electionif exit polling alone is considered.

The result is not unusual because the probabifiry4+-L&ruUp or more extreme than thesample proportion is grealer-than 5%. l[hus, it is not tmusual for a wrong call to be made in anelection if i*it prttitti' dffi.

A researcher studying public opinion of proposed Social Security changes obtains a simple randomsample of 35 adult Americans and asks them whether or not they support the proposed changes. To saythat the distribution of the sample proportion of adults who respondyes, is approximately normal, howmany more adult Americans does the researcher need to sample in the followi@tasE*r---

Student:Date:Time:

yi7./ refgrendum is 0.49? Based o4 your result, comment on the dangers of using exit polling to call,, *-----'*-t-- electio;;-- i tr.?l ?r.n -= n < I

rl53ltuo '= o,sl

How likely are the results of your sample if the population proportion of voters in the town in favor ofthe referendum is 0.49? /

n a r1;t'tu( ad{ (c:,s l, rc'\ qcl, c,rl4,c:,al1sb 17) :The probability that more thar,r 153 people voted for the referendum i5 O" ).{4L{RtiLlr-ril tr.; ii-'tl1' ti*i;it:-iai pi:rics i-ia; i1'ir,:iiiri. i

Comment on the dangers of using exit polling to call elections. Choose the correct answer below.

\,?('l -?)l,-

i ti

16.

{a) 20%of all adult Americans support the changes V C tt UJUI+ {'i';{b) 25% of all adult Americans support the chrnges , 42, \1,1 t ti ,

-*- - ,'-irr,+ )s n /

,->1 n{i cl a )i / pi ,i.i e ,l'; u*illi

;:t.Ci t3n

(a) The researcher must ask!fuore American adults. (i,lorinil :rrr rr- rh,; ttiiilii :r'ur$r;,;

(b) The researcher must ask more American adults. ii-lrili:.riJ ir1-r tii rir,*: tir-iiiJr;i. rlle 3;i ,;

,^.,o{t,T I'l ' r' t

111 rui4Ll haw( ,\ t't (c,,,JL) ( t *c';?) - {C\-,/

r,r ih:r|; -#\'=,C ,i , ,r,,!..'=rg. ''.,:'' '1i',iu')?'-

)',^!,3- i:5-=:3-'8

vi,:, b|,{.-r.'" n{'td ,18 illry /CI