
x = # of nickels
2x = # of quarters
35  3x = # of dimes ← total coins is 35
0.05x + 0.25(2x) + 0.1(35  3x) = 5 ← value of coin times number of coins equals total value
0.05x + 0.5x + 3.5  0.3x = 5 ← distributive property
0.25x + 3.5 = 5 ← combined like terms
0.25x = 1.5 ← subtracted 3.5
x = 6
2x = 12
35  3x = 17
6 nickels, 12 quarters, and 17 dimes
 Proof
