Question

You measure 33 textbooks' weights, and find they have a mean weight of 43 ounces. Assume the population standard deviation is 4.6 ounces. Based on this, construct a 90% confidence interval for the true population mean textbook weight. Give your answers as decimals, to two places License Question 4 of 7 Points possible: 1 This is attempt 1 of 1 .

Answer 1

90% Confidence Interval of true population mean:

[ $\overline{X} - \tau_{0.95} \frac{\sigma}{\sqrt{n}}$ , $\overline{X} + \tau_{0.95} \frac{\sigma}{\sqrt{n}}$ ], where, $\overline{X}$ = 43, $\sigma$ = 4.6, $\tau_{0.95}$ = 1.645,

n = 33.

= [43 - 1.3172, 43 + 1.3172] = [41.6828, 44.3172].

Hence, 41.68 < $\mu$ < 44.32. (Ans).