i. The quantity of rice and its cost are directly proportional to each other.

e.g., If 1 kg of rice price = ₹ 40. Then, 2kg of rice price = ₹ 2 × 40 = ₹ 80.

ii. The height of a tree and the number of years is neither directly nor inversely proportional to each other.

iii. Increase in cost and number of shirts that can be purchased if the budget remains the same is inversely proportional to each other.

e.g. If 2 shirt’s prices = ₹ 800. After increase in price each price.

1 shirt price becomes of ₹ 800 where budget = ₹ 800.

iv. Area of land and its cost are directly proportional to each other.

e.g. Let 200m² land cost = ₹ 5000

Then, 400m² land cost = ₹ 10,000

v. Sales tax and the amount of the bill are directly proportional to each other.

e.g. Let bill amount = ₹ 1000

Sales tax = 10

Then, sales tax =

But if, bill amount = 2000

Sales tax = 10

Then, sales tax =