TOTAL PRODUCT AND MARGINAL PRODUCT: A mathematical connection between marginal product and total product stating that marginal product IS the slope of the total product curve. If the total product curve has a positive slope (that is, is upward sloping), then marginal product is positive. If the total product curve has a negative slope (downward sloping), then marginal product is negative. If the total product curve has a zero slope (horizontal), then marginal product is zero. Moreover, if the total product curve has a positive and increasingly steeper slope, then the marginal product is positive and rising. If the total product curve has a positive and decreasingly steeper slope, then the marginal product is positive but falling.

     See also | total product | marginal product | short-run production | slope | total-marginal rule | average-marginal rule | law of diminishing marginal returns | increasing marginal returns | decreasing marginal returns |