You want to estimate the percentage of statistics students w

You want to estimate the percentage of statistics students who get grades of C or better. How many students should you survey to be 95% confident that the sample percentage is off by no more than 2 percentage points.

*Must provide formula, and answer*

Solution

you need to use this equation n = (Z_(alpha/2)/(E))^2*p(1-p) Now Z(alpha/2) is 1.96 since the problem wants 95 confidence interval, the E is your margin of error which is 2 percent, p denotes your prior estimate and since the problem does not have one it is standard to use p = .5.

Now putting it all together we get n = (1.96/.02)^(2)(.5(1-.5)) = 2401