How many students

Question

SAT scores are normally distributed with a mean of 1,500 and a standard deviation of 300. An administrator at a college is interested in estimating the average SAT score of first-year students. If the administrator would like to limit the margin of error of the 96% confidence interval to 5 points, how many students should the administrator sample? Make sure to give a whole number answer.

Answer 1

Hi Courtney,

Formula for this is:

n = (z*sigma)/m)²

n= sample size—what we are looking for

z*= z-critical value =2.05 for 96% confidence—check z-table

sigma= standard deviation = 300

m= margin of error = 5

Substituting:

n = ((2.05*300)/5)²

n = 15129

I hope this helps.