Norman has a coin collection. There are 3 dimes for every 5 quarters in his collection. If Norman has a total of 72 dimes, how many quarters does he have?
43
74
102
120
If there are 3 dimes for every 5 quarters, then the ratio of dimes to quarters is 3/5.
Let x be the number of quarters.
The number of dimes is 3/5 * x = 72.
Multiplying through the equation gives x = 72 * 5 / 3 = <<72*5/3=120>>120 quarters. Answer: \boxed{120}.