Question

Power+, produces AA batteries used in remote-controlled toy cars. The mean life of these batteries follows the normal probability distribution with a mean of 33 hours and a standard deviation of 5.2 hours. As a part of its testing program, Power+ tests samples of 36 batteries. Use Appendix B.1 for the z-values.

a. What can you say about the shape of the distribution of sample mean?

Shape of the distribution is:

b. What is the standard error of the distribution of the sample mean? (Round the final answer to 4 decimal places.)

Standard error:

c. What proportion of the samples will have a mean useful life of more than 34 hours? (Round the final answer to 4 decimal places.)

Probability:

d. What proportion of the sample will have a mean useful life greater than 32.5 hours? (Round the final answer to 4 decimal places.)

Probability:

e. What proportion of the sample will have a mean useful life between 32.5 and 34 hours? (Round the final answer to 4 decimal places.)

Probability:

Answer 1