posted by Tykrane on .
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 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 tires 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.