Background data: Norman Bates has just inherited $40,000. Consultants identified guest showers as the most significant use of water. They calculated that the lengths of guest showers at the Bates Motel are normally distributed with a mean of 10 minutes and a standard deviation of 3 minutes.

Question: What is the probability that a randomly selected shower took more than 12 minutes?

Please answer the question using excel. Please write out the excel formulas and calculations used in getting the answer.