The repair cost for a certain model of laptop computer has a normal distribution with a mean of $100, and with a standard deviation of $25. If 16 ovens are sent for repairs, find the probability that the average cost of repairs will be within $10 of the mean.

Answer 1

It would help if you proofread your questions before you posted them.

Have no data on ovens.

Z = (score-mean)/SEm

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to Z.