You want to know if there's a difference between the proportions of high-school students and college students who read newspapers regularly. Out of a random sample of 500 high-school students, 287 say they read newspapers regularly, and out of a random sample of 420 college students, 252 say they read newspapers regularly. Required:
a. Construct a 95% confidence interval for the difference between the proportions of high-school students and college students who read newspapers regularly. Be sure to show that you've satisfied the conditions for using a z-interval.
b. Draw a conclusion, based on your 95% confidence interval, about the difference between the two proportions.
c. If you wanted to use a test statistic to determine whether the proportion of high-school students who read newspapers regularly is significantly lower than the proportion of college students who read newspapers regularly, what would you use as your null and alternative hypotheses?