A company that receives the majority of its orders by telephone ...

[Arii_bell]

A 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 is the probability that a randomly selected caller is placed on hold fewer than 7 minutes?
 
  A) 0.9990881 B) 0.0009119 C) 0.917915 D) 0.082085

Question 2

A 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?
 
  A) 0.6321 B) 0.60810 C) 0.50 D) 0.3679

[Cnarkel]

Answer to Question 1

C

Answer to Question 2

D