A random sample of 51 of the largest companies in the united states gave the following P/e ratios

Question

11 35 19 13 15 21 40 18 60 72 9 20
29 53 16 26 21 14 21 27 10 12 47 14
33 14 18 17 20 19 13 25 23 27 5 16
8 49 44 20 27 8 19 12 31 67 51 26
19 18 32
Use a calculator with mean and sample standard deviation keys to verify that xbar = 25.2 and s=15.5
find a 99 % confidence interval for the P/E population mean of all large companies

Bank One merged with JP morgan had a P/E of 12, AT7t had a P/E of 72 Disney had a P/E of 24 Examine the confidence intervals in b and c how would you describe the stocks at the time the sample was taken

Answer 1

Find the mean first = sum of scores/number of scores

Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.

Standard deviation = square root of variance

90% = mean ± 2.575 SD

I'll let you do the calculations.

I'm not clear on what you are asking for in the last part.