A researcher is interested in estimating the mean weight of a semi tractor truck to determine the potential load capacity.She takes a random sample of 17 trucks and computes a sample mean of 20,000 pounds with sample standard deviation of 1,500.She decides to construct a 98% confidence interval to estimate the mean.The degrees of freedom associated with this problem are _______.
A)18
B)17
C)16
D)15
E)20

Question

Quizplus · Accepted Answer

The degrees of freedom for a confidence interval based on a sample mean are calculated as the sample size minus one. Here, the sample size is 17, so the degrees of freedom are 17 - 1 = 16.

A Researcher Is Interested in Estimating the Mean Weight of a Semi