math
posted by Sarah .
The number of accidents that occur at the intersection of Pine and Linden streets between 3 pm. and 6 pm. on Friday afternoons is 0,1,2, or 3, with probabilities of 0.84, 0.13. 0.02, and 0.01. What is the expected value for the random variable given the number of accidents?

The expected value is sum of n*P(n), for all possible values of n.
0*0.84 + 1*0.13 + 2*0.02 + 3*0.01
= 0.20