STAT 200 Week 6 Homework Problems.

9.1.2 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/ = 0.582 q1=1-0.582 = 0.418 n2=211,693 p2=/ = 0.485 q1=1-0.485 = 0.515 zc = 1.645 E=1.645*sqrt[{(0.582*0.418)/}+{90.485*0.515)/}] E= 0.0028 (0.582-0.485)-0.0028<p1-p2<(0.582-0.485)+0.0028 0.0942<p1-p2<0.998 There is a 90% chance that 0.0942<p1-p2<0.998 contains true difference in proportions