2/5 - 1/3 = 6/15 - 5/15 = 1/15
3(1/15) = 3/15
6/15 + 5/15 + 3/15 = 14/15, so the four pennies are 1/15 of the total.
If 1/15 is 4, 15/15 is 60 coins total
5/15 is 20 quarters
6/15 is 24 dimes
3(24 - 20) = 12 nickles
The value is on you.