A. This is the average variable cost of producing 9 units. Marginal cost cost refers to the additional cost of production from producing one additional unit. To find the marginal cost of producing the ninth unit, one must find the total cost for producing both 8 units and 9 units of the good. The difference in total cost is the marginal cost of producing the ninth unit.
B. Marginal cost cost refers to the additional cost of production from producing one additional unit. To find the marginal cost of producing the ninth unit, one must find the total cost for producing both 8 units and 9 units of the good. The difference in total cost is the marginal cost of producing the ninth unit. This chart gives average total costs, not total costs. When doing this calculation, the marginal cost of producing the 9th unit is $25.75. The marginal cost of the 9th unit = Total cost of 9 units - Total cost of 8 units = ($33.75 × 9) - ($34.75 × 8) = $303.75 - $278.00, and the marginal cost of producing the 9th unit = $25.75.
C. This is the average variable cost of producing 8 units. Marginal cost cost refers to the additional cost of production from producing one additional unit. To find the marginal cost of producing the ninth unit, one must find the total cost for producing both 8 units and 9 units of the good. The difference in total cost is the marginal cost of producing the ninth unit.
D. This is the average cost per unit of producing 9 units. Marginal cost cost refers to the additional cost of production from producing one additional unit. To find the marginal cost of producing the ninth unit, one must find the total cost for producing both 8 units and 9 units of the good. The difference in total cost is the marginal cost of producing the ninth unit.
