A local laundry and dry cleaner collects the following data on its workforce productivity. Workers always work in teams of two, and the laundry earns $3.00 of revenue for each shirt laundered.
| Quantity of Labor (L) (Workers) | Total Product (TP) (Shirts Laundered per Hour) |
| 0 | 0 |
| 2 | 20 |
| 4 | 36 |
| 6 | 50 |
| 8 | 62 |
The marginal revenue product ($ per worker) for hiring the fifth and sixth workers is closest to:
B is correct. The marginal product (MP) is the amount of additional output resulting from using one more unit of input: ΔTP/ΔL, where ΔTP is the change in total product and ΔL is the change in total labor. The marginal revenue product (MRP) is the marginal product of an input times the price of the product: MP × Price = ΔTP/ΔL × Price.
In this problem, the marginal product of hiring the 5th and 6th workers (ΔL = 2) is 14 shirts per hour/2 workers = 7 shirts per hour/worker. With each shirt resulting in $3 of revenue, the MRP is 7 shirts per hour/worker × $3/shirt = $21 per worker.