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

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 spanide the fraction with 5. For example: $frac{3}{20} = frac{(3 imes 5)}{(20 imes 5)} = frac{15}{100}$

If the fraction has a denominator 25, we multiply and spanide the fraction with 4. For example: $frac{2}{25} = frac{(2 imes 4)}{(25 imes 4)} = frac{8}{100}$

If the fraction has a denominator 50, we multiply and spanide the fraction with 2. For example: $frac{7}{50} = frac{(7 imes 2)}{(50 imes 2)} = frac{14}{100}$

The fractions with 100 as denominator are converted to percentages. For example: $frac{75}{100}$ = 75%; $frac{40}{100}$ = 40%; $frac{70}{100}$ = 70%

Write the following fraction as a percentage

$mathbf{frac{11}{20}}$

Solution

Step 1:

The given fraction $frac{11}{20}$ has a denominator 20.

We multiply and spanide the fraction by 5

$frac{11}{20} = frac{(11 imes 5)}{(20 imes 5)} = frac{55}{100}$

Step 2:

Writing this fraction as a percentage

By definition, $frac{55}{100}$ = 55%

Step 3:

So, $frac{11}{20}$ = 55%

Write the following fraction as a percentage

$mathbf{frac{9}{25}}$

Solution

Step 1:

The given fraction $frac{9}{25}$ has a denominator 25.

We multiply and spanide the fraction by 4

$frac{9}{25} = (9 imes 4) span (25 imes 4) = frac{36}{100}$

Step 2:

Writing this fraction as a percentage

By definition, $frac{36}{100}$ = 36%

Step 3:

So, $frac{9}{25}$ = 36%

Write the following fraction as a percentage

$mathbf{frac{13}{50}}$

Solution

Step 1:

The given fraction $frac{13}{50}$ has a denominator 50.

We multiply and spanide the fraction by 2

$frac{13}{50} = (13 imes 2) span (50 imes 2) = frac{26}{100}$

Step 2:

Writing this fraction as a percentage

By definition, $frac{26}{100}$ = 26%

Step 3:

So, $frac{13}{50}$ = 26%