A purchasing agent for a trucking company is shopping for replacement tires for their trucks from two suppliers. The suppliers' prices are the same. However,Supplier A's tires have an average life of 60,000 miles with a standard deviation of 10,000 miles. Supplier B's tires have an average life of 60,000 miles with a standard deviation of 2,000 miles. Which of the following statements is true?
A)The two distributions of tire life are the same.
B)On average,Supplier A's tires have a longer life than Supplier B's tires.
C)The life of Supplier B's tire is more predictable than the life of Supplier A's tires.
D)The dispersion of Supplier A's tire life is less than the dispersion of Supplier B's tire life.

Question

Quizplus · Accepted Answer

The standard deviation of Supplier B's tire life is much smaller than Supplier A's. This means that the tire life of Supplier B is more predictable than that of Supplier A. Option A is false because the distributions are not the same as the standard deviation is different. Option B is not true because the average life is the same for both. Option D is not accurate as the standard deviation of Supplier B is smaller, meaning the tire life is more concentrated around the average.

A Purchasing Agent for a Trucking Company Is Shopping for Replacement