Converting Fractions to Percentages
(KS3, Year 7)

The Lesson

A fraction can be converted to a percentage.

How to Convert a Fraction to a Percentage

Converting a fraction to a percentage is easy. Divide the top number of the fraction by the bottom number of the fraction and then multiply by 100%.

Question

What is 15 as a percentage?

Step-by-Step:

1

Divide the top number (called the numerator) of the fraction (1) by the bottom number (called the denominator) of the fraction (5).

1 ÷ 5 = 0.2

2

Multiply the answer (0.2) by 100%.
0.2 × 100% = 20%
Don't forget: a percentage has a % ("percent") sign after it.

Answer:

15 converted to a percentage is 20%.

How to Convert a Fraction to a Percentage Using a Formula

To convert a fraction to a percentage you have to multiply the fraction by 100%.

The method for calculating this formula is exactly the same as in the example above.

Lesson Slides

The slider below gives another example of converting a fraction to a percentage. Open the slider in a new tab

Interactive Widget

Here is an interactive widget to help you learn about converting fractions to percentages.

What Is a Fraction?

Fractions consist of a numerator and a denominator.

The denominator tells you how many equal parts the whole is divided into, and the numerator tells you how many of these parts there are.

What Is a Percentage?

A percentage expresses a part of a whole number as parts out of 100. "Per cent" means "per 100" or "out of 100". A percentage is shown by the symbol %.

Why Does the Formula Work?

To convert a fraction to a percentage, the formula tells us to multiply the fraction with 100%.
Percentage = Fraction × 100%
It is a special case of finding the fraction of a number, where the number is 100%. Read more about finding the fraction of a number
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See Also

What is a fraction? What is a percentage? What is a numerator? What is a denominator? Finding the fraction of a number Learn more about converting fractions to percentages ( interactive widget)