6) Aclubprofessionalatamajorgolfcourseclaimsthatthecourseissotoughthatevenprofessionalgolfers
rarelybreakparof73.Thescoresfromarandomsampleof20professionalgolfersarelistedbelow.Findthe
teststatisticxtotesttheclubprofessionalʹsclaim.
72 70 73 73 76 75 67 79 73 78
70 72 74 74 81 79 73 75 76 66
A) 6 B) 4 C) 14 D) 10
7) Agovernmentagencyclaimsthatthemedianhourlywagesforworkersatfastfoodrestaurantsinthewestern
U.S.is$6.65.Inarandomsampleof100workers,68werepaidlessthan$ 6.65,10werepaid$6.65,andtherest
morethan$6.65.Findthecriticalvaluestotestthegovernmentʹsclaim.Useα=0.05.
A) –1.96 B) 1.96 C) –1.645 D) 2.575
8) Agovernmentagencyclaimsthatthemedianhourlywagesforworkersatfastfoodrestaurantsinthewestern
U.S.is$6.55.Inarandomsampleof100workers,68werepaidlessthan$6.55,10werepaid
$6.55,andtherestmorethan$6.55.Findtheteststatisticztotestthegovernmentʹsclaim.
A) –4.743 B) –3.912 C) –3.187 D) –2.386
9) Acollegeresearcherclaimsthatthemedianhoursworkedbyfulltimestudentsisatleast10hoursperweek.In
arandomsampleof100students,65workedmorethan10hours,10workedexactly10hoursandtherest
workedlessthan10hours.Findthecriticalvaluetotesttheresearcherʹsclaim.Useα=0.05.
A) –1.645 B) –1.96 C) –2.33 D) –2.575
10) Acollegeresearcherclaimsthatthemedianhoursworkedbyfulltimestudentsisatleast13hoursperweek.In
arandomsampleof100students,58workedmorethan13hours,10workedexactly13hoursandtherest
workedlessthan13hours.Findtheteststatistictotesttheresearcherʹsclaim.
A) -2.635 B) -2.741 C) -3.5 D) -3.6
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
Performtheindicatedsigntest.Besuretodothefollowing:Identifytheclaimmathematicallyandstatethenulland
alternativehypotheses.Determinethecriticalvalueandfindtheteststatistic.Decidewhethertorejectorfailtoreject
thenullhypothesisandinterpretthedecisioninthecontextoftheoriginalclaim.
11) Aconveniencestoreownerbelievesthatthemediannumberoflotteryticketssoldperdayis44.Arandom
sampleof20daysyieldsthedatabelow.Testtheownerʹsclaim.Useα=0.05.
27 43 54 59 26 50 65 22 28 33
42 49 49 39 39 44 44 54 49 33
12) Arealestateagentsurmisesthatthemedianrentforaone–
edroomapartmentinabeachcommunityin
southernCaliforniaisatleast$1500permonth.Therentsforarandomsampleof15one–bedroomapartments
arelistedbelow.Testtheagentʹsclaim.Useα=0.01.
$1800 $1750 $1200 $1375 $1235
$2250 $1675 $1170 $1890 $2500
$1495 $1500 $1575 $1500 $1280
13) Aclubprofessionalatamajorgolfcourseclaimsthatthecourseissotoughthatthemedianscoreisgreater
than75.Thescoresfromarandomsampleof20professionalgolfersarelistedbelow.Testtheclub
professionalʹsclaim.Useα=0.05.
74 72 75 75 78 77 69 81 75 80
72 74 76 76 83 81 75 77 78 68
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