1. 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?

The two distributions of tire life are the same.

On average, Supplier A's tires have a longer life than Supplier B's tires.

The life of Supplier B's tire is more predictable than the life of Supplier A's tires.

The dispersion of Supplier A's tire life is less than the dispersion of Supplier B's tire life.

2.What is the relationship among the mean, median, and mode in a symmetric distribution?

They are all equal.

The mean is always the smallest value.

The mean is always the largest value.

The mode is the largest value.

3.According to Chebyshev's theorem, at least what percent of the observations lie within plus and minus 1.75 standard deviations of the mean?

56%

95%

67%

100%

4.A sample of wires coming off the production line was tested for tensile strength. The statistical results (in PSI) were the following:

Arithmetic mean 500 Median 500 Mode 500 Standard Deviation 40 Quartile deviation 25 Mean deviation 32 Range 240 Sample size 100