Michael and Thomas are selling their lego collections. They agree to split any money they earn. They sell them based on how many circles are on top. Each circle costs 1 cent. They earned $5 each after selling 100 single pieces, 45 double pieces, 50 triple pieces and a number of quadruple pieces. How many quadruple pieces did they sell?
Thoughts? Step-by-step reasoning:
They made $10 because 2 x 5 = 10. They made $1 off single pieces because 100 x .01 = 1. They made $.9 off double pieces because 45 x .02 = .9. They made $1.5 off triple pieces because 50 x .03 = 1.5. They earned $3.4 off the first three types because 1 + .9 + 1.5 = 3.4. They earned $6.6 off the quadruple pieces because 10 - 3.4 = 6.6. They sold 165 quadruple pieces because 6.6 / .04 = 165.
Thus, the answer is 165.