Before deciding which of two types of stamping machines should be purchased, the plant manager of an automotive parts manufacturer wants to determine the number of units that each produces. The two...

Before deciding which of two types of stamping machines should be purchased, the plant manager of an automotive parts manufacturer wants to determine the number of units that each produces. The two machines differ in cost, reliability, and productivity. The firm’s accountant has calculated that machine A must produce 25 more nondefective units per hour than machine B to warrant buying machine A. To help decide, both machines were operated for 24 hours. The total number of units and the number of defective units produced by each machine per hour were recorded. These data are stored in the following way. Column 1 = Total number of units produced by machine A and column 2 = Number of defectives produced by machine A; column 3 = Total number of units produced by machine B; column 4 = Number of defectives produced by machine B). Determine which machine should be purchased.