In XYZ company an annual demand for a machine part is 100,000 units. The part is produced on a high-speed lathe, using 1112 screw-machine steel costing 15 per pound. A study was conducted to determine whether it might be cheaper to use brass screw stock, costing 72 per pound. Because the weight of steel required per piece was 0.0353 pounds and that of brass was 0.0384 pounds, the material cost per piece was 0.50 for steel and 75 for brass.

However, when the manufacturing engineering department was consulted, it was found that, although 57.1 defect free parts per hour were being produced by using steel, the output would be 102.9 defect-free parts per hour if brass were used. Which material should be used for this part?

Machine attendant was paid 760/hour, and the variable overhead costs for the turret were estimated to be 510/hour.