To achieve cost minimization, a firm should adjust its input factors until the ratio of the marginal product of labor to the price of labor equals the ratio of the marginal product of capital to the price of capital. This principle is known as the _____ condition.

The principle you're referring to is called the "equal marginal principle. " It states that to minimize costs, a firm should adjust how much labor and capital it uses until the additional output gained from spending one more dollar on labor is equal to the additional output gained from spending one more dollar on capital. For example, if a factory finds that hiring an extra worker produces 10 units of output for every $20 spent, while investing in new machinery produces 5 units for every $10 spent, the firm should consider hiring more workers or investing in machinery to balance these ratios. This helps ensure that the firm is using its resources in the most efficient way possible, ultimately lowering costs and increasing profit. By keeping these ratios equal, the firm maximizes productivity while minimizing expenses.