20 The discrete random variable X is the number of passengers waiting at a bus stop. The table below shows the probability distribution for the number of passengers waiting at a bus stop. What is the variance of the number of passengers at a bus stop? X 0 1 P(X) 201 40 2 30 3 Total 10 1.00 0.9 1.7 1.1 1.3 0.8 C