Question

A psychologist wants to estimate the standard deviation of IQ scores. It is widely believed that IQ scores follow a normal distribution. Her random sample of

25

IQ scores has a mean of

99

and a standard deviation of

13.2

. Find the

99%

confidence interval for the population standard deviation based on this sample. Then complete the table below.

Carry your intermediate computations to at least three decimal places. Round your answers to at least two decimal places. (If necessary, consult a list of formulas.)

What is the lower limit of the 99% confidence interval?
What is the upper limit of the 99% confidence interval?

Answer 1