A study of 60 white mice showed that their average weight was 5.7 ounces. The standard deviation of the population is 0.4 ounces. Which of the following is the 90% confidence interval for the mean weight per
White mouse?
A) (5.62, 5.78)
B) (5.50, 5.90)
C) (5.60, 5.80)
D) (5.04, 6.36)

Question

Quizplus · Accepted Answer

The 90% confidence interval for the mean weight per white mouse is (5.62, 5.78). This is because the standard deviation is 0.4 ounces, and the sample size is 60. Therefore, the margin of error is 0.4 / sqrt(60) = 0.06 ounces. The confidence interval is then (5.7 - 0.06, 5.7 + 0.06) = (5.62, 5.78).

A Study of 60 White Mice Showed That Their Average