Math
posted by Lena .
John's Collection:
10 coins in all
2 fewer quarters than dimes
2 quarters
Q =
D =
N =

Q = 2 , it said so
D = 4 , it said so
N = 4 , assuming he only had nickels, dimes and quarters, and no pennies
otherwise:
3N and 1 P
2N and 2P
1 N and 3 P
no N and 4 P