A small slot machine holds 500 coins consisting of nickels, dimes, and quarters. The number of quarters is twice the number of dimes. If the value of all the coins is $88.00, how many nickels, were in the slot machine?

Answer 1

dimes --- x
quarters -- 2x
nickels --- 500 - x - 2x or 500-3x

10x + 25(2x) + 5(500-3x) = 8800

solve for x, then found 500-3x