Question

3. Last year the American worker spent an average of 77 hours logged on to the Inter-net while at work. Assume the times are normally distributed and that the standard deviation is 20 hours. What is the probability a randomly selected worker spent fewer than 50 hours logged on to the Internet? (Round to four decimal places) What is the probability a worker spent more than 100 hours logged on to the Internet? (Round to four decimal places) A person is classified as a heavy user if he or she is in the upper 20% of usage. How many hours must a worker have logged on to the Internet to be considered a heavy user? (Round to two decimal places)

Answer 1