A sample of 40 CDs from a student's collection showed a mean length of 52.74 minutes with a standard deviation of 13.21 minutes. Construct a 95% confidence interval for the population standard deviation. (Round your answers to 4 decimal places.)

1 answer

You might try a formula like this one:

s/(1 + 1.96/√2n) to s/(1 - 1.96/√2n)

Substitute and calculate. There may be other variations of similar formulas you can use as well.