What is the law of variable proportions?
OR
Define the law of variable proportion.

Explanation

The law of variable proportion shows that as we increase the quantity of only one input, keeping other inputs fixed, the total product increases at an increasing rate in the beginning, then increases at d:imin:ishing rate and after a level of output ultimately falls. The behaviour of Total product according to this law is as under:
(i) TP increases continuously from points O to A.
(ii) It increases at an increasing rate (convex shape) from Oto P and at a diminishing rate (concave shape) from P to A.
(iii) TP is maximum at A and remains so upto point B.
(iv) After Point B, Total Product falls.