A Study Conducted by Uni-Mart, a Mail-Order Department Store, Reveals

Multiple Choice

A study conducted by Uni-Mart, a mail-order department store, reveals that the time intervals in minutes between incoming telephone calls on its toll-free 600 line between 9 A.M. and 2 P.M. are exponentially distributed with probability density function . What is the probability that the time interval between successive calls is more than 6 min? Round your answer to four decimal places. ​

A) 0.4899
B) ​0.8869
C) ​0.2950
D) ​0.1737
E) ​0.8981