The average time between phone calls arriving at a call center is 30 seconds.Assuming that the time between calls is exponentially distributed, find the probability that less than two minutes elapse between calls.
A)0.018
B)0.064
C)0.936
D)0.982
E)1.000

Question

Quizplus · Accepted Answer

The probability that less than two minutes elapse between calls is the same as the probability that the time between calls is less than two minutes. The time between calls is exponentially distributed with a mean of 30 seconds, so the probability that the time between calls is less than two minutes is:P(X < 120) = 1 - e^(-120/30) = 0.982Therefore, the correct answer is D.

The Average Time Between Phone Calls Arriving at a Call