Page 112 - Math Skill - 5

110 Maths

2. Express each of the following as a decimal.
(a) 24% (b) 75% (c) 0.35% (d) 0.3% (e) 6.25%

Value of the Percentage

To find a percentage of a given quantity, we convert the percentage into a fraction and then
multiply by the given quantity.
Let’s learn through examples.

Let’s Attempt

Example: Find the value of percentage.
(a) 12% of 240 (b) 30% of ` 250 (c) 25% of 400 km

Solution: (a) 12% of 240 (b) 30% of ` 250 (c) 25% of 400 km

12 30 25
= × 240 = × ` 250 = × 400 km
100 100 100

= 28.8 = ` 75 = 100 km

Quantity as a Percentage
Sometimes we need to find quantities in form of percentage. To do this, we write the given
quantity as numerator and total quantity as the denominator. We convert the so obtained
fraction into percentage. Let’s learn through examples.

Let’s Attempt

Example 1: What per cent of 30 is 24?
8

Solution: Fraction is 24 ⇒ Required per cent = 24 × 10 0 = 80%
30 30 10 100
Example 2: What per cent of 950 is 589?
31 2
Solution: Given fraction = 589 ⇒ Required per cent = 589 × 100 = 62%
950 950 100
Example 3: What is the number whose 18% is 27? 19

Solution: Here, 18% of required number = 27

18 × Required number = 27
100
3 50
\ Required number = 27 × 100 = 150
18
2
Thus, required number is 150