Question

If the mean rate of arrival in a restaurant is 10 customers per hour, what is the probability of having 4 customers arriving in any hour?

Answer 1

What is your measure of variability?

Answer 2

I have answer this question as follow:

P(C)=(ac*e-a)/c!=(104*e-10)/4!=
(10000*e-10)/24=(10000*2.71828-10)/24= (10000*4.5406)/24=0.45406/24=0.0185

Is it correct?