Let x be the number of the $20 dollars bills. Then the number of the $10 dollars bills is (x+2), according to the condition. The money equation is 20x + 10*(x+2) = 410 Simplify and solve for x. 20x + 10x + 20 = 410 30x = 410-20 = 390 ====> x == 13. Answer. 13 of the $20-dollars bills and 13+2 = 15 of the $10-dollars bills. Check. 20*13 + 10*15 = 410 dollars. ! Correct !