Chapter 6, Problem 9CR

Probability Distribution: Auto Leases Consumer Banker Association released a report showing the lengths of automobile leases for new automobiles. The results are as follows:

Lease Length in Months	Percent of Leases
13-24	12.7%
25-36	37.1%
37 48	28.5%
49-60	21.5%
More than 60	0.2%

(a) Use the midpoint of each class, and call the midpoint of the last class $66.5$ months, for purposes of computing the expected lease term. Also find the standard deviation of the distribution.

(b) Sketch a graph of the probability distribution for the duration of new auto leases.