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.
