Paul has four more nickels than quarters and twice as many dimes as quarters. If he has a total of $6.20, how many dimes does he have?

12 quarters, 16 nickels, 24 dimes

Step-by-step explanation:

Nickels = 4 + quarters

dimes = 2 * quarters

total $6.20 = 0.25quarters + 0.1 dimes + 0.05nickels

6.20 = 0.25q + 0.1d + 0.05n

6.20 = 0.25q + 0.1 * (2q) + 0.05 (4 + q)

6.2 = 0.25q + 0.2q + 0.2 + 0.05q

6.2 = 0.45q + 0.2 + 0.05q

6.2 = 0.5q + 0.2

6 = 0.5q

q = 12

12 quarters, 16 nickels, 24 dimes