Question

Police response time to an emergency call is the difference between the time the call is first received by the dispatcher and the time a patrol car radios that it has arrived at the scene. Over a long period of time, it has been determined that the police response time has a normal distribution with a mean of 10.4 minutes and a standard deviation of 1.7 minutes. For a randomly received emergency call, find the following probabilities. (For each answer, enter a number. Round your answers to four decimal places.)

(a)

the response time is between 7 and 12 minutes

(b)

the response time is less than 7 minutes

(c)

the response time is more than 12 minutes

Answer 1

The response time is normally distributed with,

(a)

The probability that the response time is between 7 and 12 minutes is obtained by calculating the z score,

(In excel use function =NORM.S.DIST(0.9412,TRUE) - NORM.S.DIST(-2,TRUE) )

(b)

The probability that the response time is less than 7 minutes is,

(c)

The probability that the response time is more than 12 minutes