In an experiment, college students were given either four quarters or a $1 bill and they could either keep the money or spend it on gum. The results are summarized in the table. Complete parts (a) through (c) below.

Purchased Gum
Kept the Money

Students Given Four Quarters
3333
1515

Students Given a $1 Bill
1717
3434

a. Find the probability of randomly selecting a student who spent the money, given that the student was given a $1 bill.

The probability is
nothing.
(Round to three decimal places as needed.)
b. Find the probability of randomly selecting a student who kept the money, given that the student was given a $1 bill.

The probability is
nothing.
(Round to three decimal places as needed.)
c. What do the preceding results suggest?