13) Aspinnerismountedonapieceofcardboarddividedintosixareasofequalsize.Eachofthesixareasisa
differentcolor(blue,yellow,red,green,whiteandorange).Whenthespinnerisspun,eachcolorshouldbe
selectedbythespinnerapproximately1
6ofthetime.Astudentsuspectsthatacertainspinnerisdefective.The
suspectedspinnerisspun90times.Theresultsareshownbelow.Findthecriticalvalueχ2
0totestthe
studentʹsclaim.Useα=0.10.
Color Blue Yellow Red Green White Orange
Frequency 12 11 16 19 17 15
A) 9.236 B) 1.610 C) 10.645 D) 11.071
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
14) Aspinnerismountedonapieceofcardboarddividedintosixareasofequalsize.Eachofthesixareasisa
differentcolor(blue,yellow,red,green,whiteandorange).Whenthespinnerisspun,eachcolorshouldbe
selectedbythespinnerapproximately1
6ofthetime.Astudentsuspectsthatacertainspinnerisdefective.The
suspectedspinnerisspun90times.Theresultsareshownbelow.Testthestudentʹsclaim.Useα
=0.10.
Color Blue Yellow Red Green White Orange
Frequency 12 11 17 16 19 15
MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion.
15) Arandomsampleof160carpurchasesareselectedandcategorizedbyage.Theresultsarelistedbelow.The
agedistributionofdriversforthegivencategoriesis18%fortheunder26group,39%forthe26 –45group,31%
forthe45–65group,and12%forthegroupover65.Calculatethechi–squareteststatisticχ2totesttheclaim
thatallageshavepurchaseratesproportionaltotheirdrivingrates.Useα
=0.05.
Age Under26 26–45 46–65 Over65
Purchases 66 39 25 30
A) 75.101 B) 85.123 C) 101.324 D) 95.431
16) Arandomsampleof160carpurchasesareselectedandcategorizedbyage.Theresultsarelistedbelow.The
agedistributionofdriversforthegivencategoriesis18%fortheunder26group,39%forthe26–45group,31%
forthe45–65group,and12%forthegroupover65.Findthecriticalvalueχ2
0totesttheclaimthatallages
havepurchaseratesproportionaltotheirdrivingrates.Useα=0.05.
Age Under26 26–45 46–65 Over65
Purchases 66 39 25 30
A) 7.815 B) 6.251 C) 11.143 D) 9.348
SHORTANSWER.Writethewordorphrasethatbestcompleteseachstatementoranswersthequestion.
17) Arandomsampleof160carpurchasesareselectedandcategorizedbyage.Theresultsarelistedbelow.The
agedistributionofdriversforthegivencategoriesis18%fortheunder26group,39%forthe26–45group,31%
forthe46–65group,and12%forthegroupover65.Testtheclaimthatallageshavepurchaserates
proportionaltotheirdrivingrates.Useα=0.05.
Age Under26 26–45 46–65 Over65
Purchases 66 39 25 30
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