Acatalog company that receives the majority of its orders by telephone conducted a study to determine how long customers were willing to wait on hold before ordering a product. the length of waiting time was found to be a variable best approximated by an exponential distribution with a mean length of waiting time equal to 2.8 minutes (i. e. the mean number of calls answered in a minute is 1/2.8). what proportion of callers is put on hold longer than 2.8 minutes?

0.3679

Step-by-step explanation:

The cumulative distribution function for exponential distribution is :-

, where  is the mean of the distribution.

Given :  A mean length of waiting time equal minutes

i.e. Mean number of calls answered in a minute

Now, the proportion of callers is put on hold longer than 2.8 minutes is given by :_

Hence, the proportion of callers is put on hold longer than 2.8 minutes = 0.3679

191 students play sports and ninety-seven 10th graders were surveyed.

step-by-step explanation: