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Think and Answer
A sweet maker uses the following ingredients to make Besan laddoos: 30% besan, 40% sugar, and
the rest part is desi ghee. What percent of desi ghee does he use to make the laddoos?

Estimation of Area of a Figure

With the help of percentages, we can estimate the part of the area of a figure.

For example: In the adjoining figure, a circle has been divided into 5 equal parts,
and out of 5 parts, 2 parts are shaded.
Here, we can estimate the percentage of the shaded part of the whole figure, as


2 =  2 × 100 % = 40%


5  5  Think and Answer
Hence, we can say that 40% area of the figure is shaded. What per cent of tangram is shaded?
1
Use of Percentages 16 1
4
1 1
8 1 4
Interpreting Percentages 16
1 1
Let us interpret the following statements: 8 8
• Nakul’s father saves 15% of his income.
• 88% of the articles in the shop are made of recycled items.
• Cheeku saves 12% of his pocket money every week.

What can you infer from each of these statements?
15
By 15%, we mean 15 parts out of 100, or we write it as . It means Nakul’s father is saving `15 out
100
of every `100 that he earns. In the same way, there are 88 articles out of every 100 in the shop that
are made by the recycled items. And Cheeku saves `12 out of every `100 from his pocket money.

Converting Percentages to “How Many”

To Find the Quantity of a Given Percentage

Nakul (to Cheeku): Suppose, in your class, there are 40 childrens and 75% of them like to play
football. Can you tell how many children like to play football in your class?
Let us try to find out the quantity of the given percentage.

Since, the total number of children in your class is 40 and 75% of 40 children like playing football.
75
Therefore, the required number of children who like playing football = × 40 = 30 children.
100

Thus, 30 children out of 40 like to play football.
Example 9: Find:
(a) 4% of 250 (b) 8.5% of 920 (c) 18% of 180 kg (d) 15% of 1 hour

223 Percentage and Its Applications