Converting a Fraction to a Percentage Denominator of 20, 25, or 50

Introduction

Consider any fraction with a denominator of 20, 25 or 50. Such fractions can be converted to fractions with a denominator of 100. Then it would be easy to write those fractions as percentages as shown below in examples.

Rules to convert a fraction into a percentage with 20, 25 or 50 as denominator

• If the fraction has a denominator 20, we multiply and divide the fraction with 5. For example: 320=(3×5)(20×5)=15100320=(3×5)(20×5)=15100
• If the fraction has a denominator 25, we multiply and divide the fraction with 4. For example: 225=(2×4)(25×4)=8100225=(2×4)(25×4)=8100
• If the fraction has a denominator 50, we multiply and divide the fraction with 2. For example: 750=(7×2)(50×2)=14100750=(7×2)(50×2)=14100
• The fractions with 100 as denominator are converted to percentages. For example: 7510075100 = 75%; 4010040100 = 40%; 7010070100 = 70%

Example 1

Write the following fraction as a percentage

11201120

Solution

Step 1:

The given fraction 11201120 has a denominator 20.

We multiply and divide the fraction by 5

1120=(11×5)(20×5)=551001120=(11×5)(20×5)=55100

Step 2:

Writing this fraction as a percentage

By definition, 5510055100 = 55%

Step 3:

So, 11201120 = 55%Example 2

Write the following fraction as a percentage

925925

Solution

Step 1:

The given fraction 925925 has a denominator 25.

We multiply and divide the fraction by 4

925=(9×4)÷(25×4)=36100925=(9×4)÷(25×4)=36100

Step 2:

Writing this fraction as a percentage

By definition, 3610036100 = 36%

Step 3:

So, 925925 = 36%Example 3

Write the following fraction as a percentage

13501350

Solution

Step 1:

The given fraction 13501350 has a denominator 50.

We multiply and divide the fraction by 2

1350=(13×2)÷(50×2)=261001350=(13×2)÷(50×2)=26100

Step 2:

Writing this fraction as a percentage

By definition, 2610026100 = 26%

Step 3:

So, 13501350 = 26%