Question

I report if u guess or answer randomly. Which confidence level would produce the widest interval when estimating the mean of a population from the mean and standard deviation of a sample of that population?

A.
54%
B.
61%
C.
38%
D.
26%

Answer 1

B. 61%

Explanation:

When we have the standard deviation of a sample, we use the t-distribution.

The width of an interval is related to the margin of error, which is given by the following equation:

M = T*s

In which T is related to the confidence level(and the sample size) and s is the standard deviation of the sample. Higher confidence levels have higher values of T.

A higher margin of error means that the interval is wider. To have a higher margin of error, we desire a higher value of T, which is achieved with a higher confidence level.

So the correct answer is:

B. 61%