By what per cent is Rs. 2,000 less than Rs. 2,400 ?

The species diversity of plants (22 per cent) is much less than that of Animals (72 per cent). What could be the explanations to how animals achieved greater diversification?

Sohan bought a second hand refrigerator for Rs 2,500, then spent Rs 500 on its repairs and sold it for Rs 3,300. Find his loss or gain per cent.

Tell what is the profit or loss in the following transactions. Also find profit per cent or loss per cent in each case. A refrigerater bought for Rs.12,000 and sold at Rs.13,500.

A manufacture makes two products A and B. product A sells at Rs.200 per unit and takes 30 minute to make. Product B sells at Rs.300 per unit and takes 1 hour to make. There is a permanent order of 14 units of product A and 16 unit of product B. A working week consists of 40 hours of production and the weekly turnover must not be less than Rs.10,000. if he profit on each unit of product A is Rs.20 and on product B is Rs.30, then find how many units of each product should be produced to get maximum profit. also find the maximum profit. solve the problem graphically.