STAT 200 Week 6 Homework Problems-Many high school students take the AP tests in different subject areas. In 2007, of the 144,796 students who took the biology exam 84,199 of them were female. In that same year, of the 2
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STAT 200 Week 6 Homework Problems-Many high school students take the AP tests in different subject areas. In 2007, of the 144,796 students who took the biology exam 84,199 of them were female. In that same year, of the 211,693 students who took the calculus AB exam 102,598 of them were female ("AP exam scores," 2013). Estimate the difference in the proportion of female students taking the biology exam and female students taking the calculus AB exam using a 90% confidence level.
n1=144,796 p1=84199/144796 = 0.582
q1=1-0.582 = 0.418
n2=211,693 p2=102598/211693 = 0.485
q1=1-0.485 = 0.515
zc = 1.645 E=1.645*sqrt[{(0.582*0.418)/144796}+{90.485*0.515)/211693}]
E= 0.0028
(0.582-0.485)-0.0028
0.05, accept Ho.
9.2.6
The British Department of Transportation studied to see if people avoid driving on Friday the 13th. They did a traffic count on a Friday and then again on a Friday the 13th at the same two locations ("Friday the 13th," 2013). The data for each location on the two different dates is in table #9.2.6. Estimate the mean difference in traffic count between the 6th and the 13th using a 90% level.
Table #9.2.6: Traffic Count
Dates 6th 13th
1990, July 139246 138548
1990, July 134012 132908
1991, September 137055 136018
1991, September 133732 131843
1991, December 123552 121641
1991, December 121139 118723
1992, March 128293 125532
1992, March 124631 120249
1992, November 124609 122770
1992, November 117584 117263
Dates 6th 13th d=x1-x2
1990, July 139246 138548 698
1990, July 134012 132908 1104
1991, September 137055 136018 1037
1991, September 133732 131843 1889
1991, December 123552 121641 1911
1991, December 121139 118723 2416
1992, March 128293 125532 2761
1992, March 124631 120249 4382
