Question

A sample of 7 adult elephants has an average weight of 12,800 pounds. the standard deviation for the sample was 21 pounds.find the 99% confidence interval of the population mean for the weight of adult elephants.assume the value is normally distributed. use a graphing calculator and round up answer to the nearest whole number.

Answer 1

Given:

n = 7, Sample mean = = 12800, Sample standard deviation (S) = 21,

Confidence level = 99% = 0.99

Therefore, = 1 - Confidence level = 1 - 0.99 = 0.01

Degrees of freedom = n-1 = 7-1 = 6

Critical value:

                    ................Using t table

99% Confidence interval: