Answer: 20 nickels and 6 quarters.
Step-by-step explanation:
Let q be equal to quarters and n be equal to nickels. We will write a system of equations to help us solve.
First, we know each quarter is $0.25 and each nickel is $0.05.
0.25q + 0.05n = 2.5
Next, we know there are 14 more nickels than quarters.
n = q + 14
We will plug the second equation into the first and solve.
0.25q + 0.05n = 2.5
0.25q + 0.05(q + 14) = 2.5
0.25q + 0.05q + 0.7 = 2.5
0.3q = 1.8
q = 6
Joan has 6 quarters. We know he has 14 more nickels than quarters, so we will use addition.
6 + 14 = 20 nickels