Confidence Intervals - Means

Question

You measure 26 textbooks' weights, and find they have a mean weight of 62 ounces. Assume the population standard deviation is 5 ounces. Based on this, construct a 95% confidence interval for the true population mean textbook weight.

Answer 1

Hi there,

in order to construct a confidence interval, all you have to do is use this simple formula:

CI = [x - CV(s/sqrt(n))], [x+ CV(s/sqrt(n))]

x = mean weight (62)

CV = critical value (in this case, it is equal to 1.96 because this is a 95% confidence interval

s = standard deviation (5)

n = number of items (26)

Please let me know if you have any further questions!