Mary has 4 dimes 5 quarters and 3 nickels and4 pennies in he

Mary has 4 dimes, 5 quarters and 3 nickels and4 pennies in her purse. She reaches in her purse and pulls out a coin without looking at what it is. Answer the following questions and give your answer as a fraction.

a. What is the probability that she pulls a nickel?

b. She puts the coin she pulled in her son

Solution

Note that there are 16 coins total for the following.

a. The probability is 3 / 16.

b. The probability is 5 / 15, because there is one fewer total coins left.

c. The probability is 4 / 15.

d. 4 / 14 = 2 / 7