Exhibit 6-5.The mean travel time to work is 25.2 minutes (U.S.Census 2010).Further,suppose that commute time follows a log-normal distribution with a standard deviation of 10 minutes. Refer to Exhibit 6-5.What is the probability a randomly selected U.S.worker has a commute time of less than 20 minutes?
A)30.15%
B)34.09%
C)65.91%
D)69.85%

Question

Quizplus · Accepted Answer

The log-normal distribution is skewed, and the mean is greater than the median. Given the mean is 25.2 minutes and the standard deviation is 10 minutes, the probability of a commute time less than 20 minutes is approximately 34.09%.