Question: A sales representative who visits customers at home finds she sells 0, 1, 2, 3, or 4 items according to the following frequency distribution.

Items sold Frequency

0 8

1 10

2 3

3 2

4 1

Find the probability that she sells the following.

a. Exactly 1 item

b. More than 2 items

c. At least 1 item

d. At most 3 items