Question

SAT scores of students at an Ivy League college are distributed with a standard deviation of 250 points. Two statistics students, Raina and Luke, want to estimate the average SAT score of students at this college as part of a class project. They want their margin of error to be no more than 25 points.(a) Raina wants to use a 90% condence interval. How large a sample should she collect?Raina should sample at least people.

Answer 1

The sample size should be 273 students

Explanation:

Here Raina wants to use 90% interval then

ME = z. SE

SE = s d/√n at end

ME/z = s d/√n

n={z.sd/ME)²

Z = 1.65 =>due to 90%confidence interval

ME= 24

sd=250

putting these value in the question we get 273 students