# Question: A professor of statistics noticed that the marks in his

A professor of statistics noticed that the marks in his course are normally distributed. He has also noticed that his morning classes average 73%, with a standard deviation of 12% on their final exams. His afternoon classes average 77%, with a standard deviation of 10%.What is the probability that the mean mark of four randomly selected students from a morning class is greater than the average mark of four randomly selected students from an afternoon class?

**View Solution:**## Answer to relevant Questions

The manager of a restaurant believes that waiters and waitresses who introduce themselves by telling customers their names will get larger tips than those who donâ€™t. In fact, she claims that the average tip for the former ...Draw a sampling distribution of a biased estimator.The number of cars sold annually by used car salespeople is normally distributed with a standard deviation of 15. A random sample of 15 sales-people was taken, and the number of cars each sold is listed here. Find the 95% ...A statistics professor is in the process of investigating how many classes university students miss each semester. To help answer this question, she took a random sample of 100 university students and asked each to report ...Review the results of Exercise 10.43. Describe what happens to the sample size whena. The population standard deviation decreases.b. The confidence level decreases.c. The bound on the error of estimation decreases.Post your question