Recall that the expected value is another way to refer to . What is really being asked is how many calls are expected to come in during a 5-minute interval.

The following conversion factor can be used to find the mean number of calls per minute when given the mean number of calls per hour.

calls hour1 hour60 minutes

Convert 36 calls per hour to calls per minute.

36 calls hour1 hour60 minutes= ________ calls per minute

To find the expected number of calls per a 5-minute interval, multiply the mean number of calls per minute by 5.

(5 minutes)(mean number of calls per minute)=5(_______)

=_________ calls per 5 minutes