Question

A random sample of 130 students is chosen from a population of 4,500 students. If the mean IQ in the sample is 120 with a standard deviation of 5, what is the 99% confidence interval for the students' mean IQ score?

Answer 1

Answer choices are
118.87–121.13
107.12–132.88
125–135
115–125

Answer 2

@AZ

Answer 3

\( \large CI = \bar{x} \pm z \frac{s}{\sqrt{n}} \)

\(\bar{x}\) is your mean which is 120

z is the z-value
and for a 99% confidence interval, the value would be 2.58
http://www.ltcconline.net/greenl/courses/201/Estimation/smallConfLevelTable.htm

and 's' is the standard deviation of 5

n is how many samples you have which is 130

Answer 4

so can you calculate the 99% confidence interval now?