Let the number of nickels be x; then the number of dimes is (2x+2) and the number of quarters is the rest coins, i.e. (12-x - (2x+2)) = 10-3x. Next, I write the total money equation 5x + 10*(2x+2) + 25*(10-3x) = 120 cents. Simplify 5x + 20x + 20 + 250 - 75x = 120 -50x = - 150 x = 3. ANSWER. 3 nickels, 2*3+2 = 8 dimes and the rest coins, i.e. 12 - 3 - 8 = 1, is/(are) quarters.