The H&S Motor Company has a direct manufacturing cost per unit of $$30,$ and motors that are of inferior quality can be reworked for $$12$ per unit. $100$ motors are produced daily, $80\%$ on average are of good quality and $20\%$ are defective. Of the defective, half can be reworked to yield good$-$quality products. Through its quality management program, the company has discovered a problem in its production process, that, when corrected $($at a minimum cost$),$ will increase the good$-$quality products to $90\%.$

The company wants to assess the impact on the direct cost per unit of improvement in product quality.