Refer to Exercise 7.93. The package of Sylvania CFL 65-watt replacement bulbs that use only 16 watts

Question:

Refer to Exercise 7.93. The package of Sylvania CFL 65-watt replacement bulbs that use only 16 watts claims that these bulbs have an average life of 8000 hours. Assume that the lives of all such bulbs have a normal with a mean of 8000 hours and a standard deviation of 400 hours. Find the probability that the mean life of a random sample of 25 such bulbs is
a. Less than 7890 hours
b. Between 7850 and 7910 hours
c. Within 130 hours of the population mean
d. Less than the population mean by 150 hours or more Distribution
The word "distribution" has several meanings in the financial world, most of them pertaining to the payment of assets from a fund, account, or individual security to an investor or beneficiary. Retirement account distributions are among the most...