A researcher is interested in estimating the mean weight of a semi tracker 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.The 90% confidence interval for the population mean rod length is ______________.
A)19,365 to 20,635
B)19,367 to 20,633
C)19,514 to 20,486
D)19,515 to 20,485
E)18,500 to 21,500

Question

Quizplus · Accepted Answer

The correct answer is A because the 90% confidence interval for the population mean rod length is 19,365 to 20,635. This is calculated using the formula: sample mean +/- (z-score * sample standard deviation / square root of sample size). The z-score for a 90% confidence interval is 1.645.

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