Page 114 - Maths On the GO Class 5

Converting Fractions into Percentages
To convert a fraction into a percentage, multiply the fraction by 100 and put the % sign.

Example : Convert the following fractions into percentages :
4 6 1
(a) (b) (c)
5 20 8
4 4 400
Solution : (a) = ´100% = % =80%
5 5 5

6 6 600
(b) = ´100% = % =30%
20 20 20
1 1 100 25 1
(c) = ´100% = % = % =12 %
8 8 8 2 2

Converting Percentages into Decimals
To convert a percentage into a decimal, ignore the % sign and divide the given number by 100.

Ex am ple : Con vert the fol low ing per cent ages into dec i mals :
(a) 45% (b) 6.9% (c) 23.8%

.
45 6 9 238
.
So lu tion : (a) 45% = =0 45 (b) 6.9% = =0 069 (c) 23.8% = =0 238
.
.
.
100 100 100
Converting Decimals into Percentages
To convert a decimal into a percentage, multiply the decimal by 100 and put the % sign.
Ex am ple : Con vert the fol low ing dec i mals into per cent ages :
(a) 0.4 (b) 0.06 (c) 0.009
So lu tion : (a) 0.4 = 0.4 × 100% = 40%

(b) 0.06 = 0.06 × 100% = 6%
(c) 0.009 = 0.009 × 100% = 0.9%

Finding Percentage of a Number

To find the percentage of a number, convert the given percentage into a fraction and then multiply it by the
given number.
Ex am ple : Find the value of 20% of 250.

20 5000
So lu tion : 20% of 250 = ´250 = =50
100 100

First express the number in the form of a fraction and then convert it into a percentage.
Ex am ple : What per cent of 20 is 15?

15 15 1500
So lu tion : = ´100% = % =75%
20 20 20

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