A Portfolio Manager Was Analyzing the Price-Earnings Ratio for This

True/False

A portfolio manager was analyzing the price-earnings ratio for this year's performance.His boss said that the average price-earnings ratio was 20 for the many stocks,which his firm had traded,but he felt that figure was too high.The portfolio manager randomly selected a sample of 50 P/E ratios and found a mean of 18.17 and standard deviation of 4.60.Assume that the population is normally distributed and test at the 0.01 level of significance.
The decision rule is: Reject H₀ if the calculated z > 2.33.