The mean of the commute time to work for a resident of Boston is 27.1 minutes. Assume that the standard deviation of the commute time is 8.3 minutes.
a) What is the minimum percentage of commuters in Boston has a commute time within 2 standard deviation of themean?
b) What minimum percentage of commuters in Boston has a commute time within 1.6 standard deviation of the mean?
c) What are the commute times within 1.4 standard deviation?