Fifteen items or less: The number of customers in line at a supermarket express checkout counter is a random variable with the following probability distribution. 0 2 3 4 5 P(x) 0.10 0.20 0.30 0.20 0.15 0.05 Send data to Excel Part: 0 / 3 Part 1 of 3 (a) Compute the mean U . Round the answer to two decimal places. X 5