Which of the following statements about the marginal product (MP) of an input is NOT correct?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → MP is the output per unit of that input.
Output per unit of an input is the average product, not the marginal product. MP is the change in output from one more unit.
Option (1) MP is the output per unit of that input. — False. This is the meaning of average product.
Option (2) MP is undefined at zero level of input employment. — True. An input cannot be negative, so there is no change from a unit before zero.
Option (3) The sum of the MPs of every unit up to a level gives the total product at that level. — True. Each MP is the output added by one unit, so adding them gives TP.
Option (4) MP is the change in output per unit of change in the input, other inputs held constant. — True. This is the meaning of marginal product.
NCERT (2026-27): “3.3.2 Average Product Average product is defined as the output per unit of variable input. … Values in this column are obtained by dividing TP (column 2) by L (Column 1). …” “3.3.3 Marginal Product Marginal product of an input is defined as the change in output per unit of change in the input when all other inputs are held constant. …” “3.3.3 Marginal Product … Since inputs cannot take negative values, marginal product is undefined at zero level of input employment. For any level of an input, the sum of marginal products of every preceeding unit of that input gives the total product. So total product is the sum of marginal products.” |