Chapter 8.1, Problem 27E

WAITNG LINES The accompanying data were obtained in a study conducted by the manager of SavMore Supermarket. In this study, the number of customers waiting in line at the express checkout at the beginning of each 3-min interval between 9 A.M. and 12 noon on Saturday was observed.

Customers	0	1	2	3	4	5	6	7	8	9	10
Frequency of Occurrence	1	4	2	7	14	8	10	6	3	4	1

a. Find the probability distribution of the random variable $X$, where $X$ denotes the number of customers observed waiting in line.

b. Draw the histogram representing the probability distribution.

c. Find the probability that the number of customers waiting in any 3-min interval between 9 A.M. and 12 noon is between 1 and 3, inclusive.