We could say that dimes = x and quarters = 60 -x
Then we use the value of the coins
10(x) + 25(60-x) = 945
I did 945 because I am doing this in cents not dollars but the answer would still work because it is asking for the amount of coins.
10x + 1500 - 25x = 945
-15x = -555
x = 37
Dimes = x = 37
Quarters = 60 - x = 60 -37 = 23
