Let x be the random variable representing the number of calls received in an hour by a 911 emergency service. a portion of the probability distribution of x is given below. value of x 0 1 2 3 4 probability p(x) 0.25 0.10 0.05 suppose the probability that x = 1 and the probability that x = 2 are the same. what are these probabilities? what is the expected number of 911 calls in an hour?
For any distribution, the sum of the probabilities of all possible outcomes must be 1. In this case, we have to have
We're told that , and we're given other probabilities, so we have
The expected number of calls would be
$110.00 divided by 4
the slope of the line is 60
one point on the line is (40,10)
in the equation outside the parenthesis the equation always tells you the slope. in this case it is 60.
in the parenthesis is also says 40 which is x because it is near the x and 10 is y because it is near y.