**Chapter 9 Direct Proportion and Inverse Proportion Set 9.1**

Question 1.

If 7 kg onions cost Rs 140, how much must we pay for 12 kg onions?

Solution:

Let the cost of 12 kg onions be Rs x.

The quantity of onions and their cost are in direct proportion.

= 240

We must pay Rs 240 for 12 kg onions.

Question 2.

If Rs 600 buy 15 bunches of feed, how many will Rs 1280 buy?

Solution:

Let the bunches of feed bought for Rs 1280 be x.

The quantity of feed bought and their cost are in direct proportion.

∴ 32 bunches of feed can be bought for Rs 1280.

Question 3.

For 9 cows, 13 kg 500 g of food supplement are required every day. In the same proportion, how much will be needed for 12 cows?

Solution:

Let the food supplement required for 12 cows be x kg.

The quantity of food supplement required and the number of cows are in direct proportion.

∴ x = 18

∴ The food supplement required for 12 cows is 18 kg.