The relation between marginal product and total product is described as below –

a) When Total Product increases at an increasing rate Marginal Product increases.

b) When Total Product increases at a decreasing rate Marginal Product decreases but it is positive.

c) When Total Product is maximum and constant Marginal Product becomes zero.

d) When Total Product falls Marginal Product becomes negative

Let's go through the following product schedule to understand it –

• From point A – B & B – C, The Total Product is increasing at an increasing rate so the Marginal Product is also increasing.

• From point C – D & D – E, The Total Product is increasing at a decreasing rate so the Marginal Product is decreasing.

• From point E – F, The Total Product is constant so the Marginal Product is zero.

• From point F – G & G – H, The Total Product is decreasing so the Marginal Product is negative.

The following graph will make it easier to understand –