1. Let R be the event that it is a rainy day and let U be the event that I brought my umbrella to the office. We know that P(R^c) = 19/20, P(U) = 3/40 and P(U | R) = 3/4. What is the probability that it is a rainy day if you see my umbrella in the office? Write your answer in the box provided and show any working below. [2 marks] Solution.