## Unitary Method

**1. Basic concept**

• If the cost of 20 m cloth = Rs 1000

The cost of 1m cloth = Rs 1000÷20

= Rs 50

So, the cost of 10 m cloth = Rs 50×10

= Rs 500

In above example the cost of 1m cloth is first obtained and then the cost of 10m cloth is found

This method of finding one is called **unitary method**

In same way below example is done

• If 15 pens cost = Rs 150

The cost of 1 pen = Rs 150÷15

= Rs 10

The cost of 20 pens = Rs 10×20

= Rs 200

**Try yourself**

1. The cost of 4 articles is Rs 72. Find the cost of 1 article?

2. 2.25m cloth is required for 1 shirt. The cloth required for 3 shirts?

3. For 8 days a family requires Rs 320 then for 4 days the family requires?

4. A man earns Rs 400 in 10 days. How much will he earn in 28 days?

5. Weight of 8 articles is 4.8 kg. What is the weight 11 such articles?

Understanding Shapes