The following figures relate to a manufacturing company producing a wide range of products which may be classified into three main groups:

Product Group

Annual Sales Rs.

Variable Cost Rs.

L

3,00,000

1,00,000

M

3,00,000

2,00,000

N

3,50,000

3,00,000

Fixed costs are (total) Rs. 2,50,000.

You are required to plot on a graph the marginal income slopes for the product groups in an alphabetical order to enable you to plot the average marginal income slope for the total output.