The average product (AP) schedule of labour is given below. Total product is zero when no labour is employed.
| Labour (units) | 1 | 2 | 3 | 4 |
|---|---|---|---|---|
| AP (units) | 10 | 12 | 12 | 11 |
Consider the following statements:
(A) The total product of 3 units of labour is 36 units.
(B) The marginal product of the 2nd unit of labour is 14 units.
(C) The marginal product of the 4th unit of labour is 11 units.
(D) The marginal product of the 3rd unit of labour is equal to the AP at 3 units.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A), (B) and (D) only
First get TP from AP (TP = AP × L), then MP as the change in TP.
\( \displaystyle TP: 10 \times 1 = 10, \ 12 \times 2 = 24, \ 12 \times 3 = 36, \ 11 \times 4 = 44 \)
\( \displaystyle MP: 10, \ 24 - 10 = 14, \ 36 - 24 = 12, \ 44 - 36 = 8 \)
(A) The total product of 3 units of labour is 36 units. — Correct. TP at 3 units = 12 × 3 = 36.
(B) The marginal product of the 2nd unit of labour is 14 units. — Correct. MP of the 2nd unit = 24 − 10 = 14.
(C) The marginal product of the 4th unit of labour is 11 units. — Incorrect. The MP of the 4th unit is 44 − 36 = 8. 11 is the AP at 4 units.
(D) The marginal product of the 3rd unit of labour is equal to the AP at 3 units. — Correct. MP of the 3rd unit is 12, and AP at 3 units is also 12.
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 … Values in this column are obtained by dividing change in TP by change in L. For example, when L changes from 1 to 2, TP changes from 10 to 24. MPL= (TP at L units) – (TP at L – 1 unit) Here, Change in TP = 24 -10 = 14 Change in L = 1 Marginal product of the 2nd unit of labour = 14/1 = 14” |