The Lesson

A fraction of a number lets us find part of a number. Imagine 3/5 (three-fifths) of a class of 25 students love mathematics. 15 students (3/5 of 25) love mathematics.

How to Find the Fraction of a Number

To find the fraction of a number you have to multiply the fraction by the number:fraction_of_number_formulaHint: 'of' means '×' when finding a fraction of a number.

A Real Example of How to Find the Fraction of a Number

Question

What is 35 of 25?

Step-by-Step:

1

Write a fraction of a number as a fraction × a number, like the formula above. In our example, the fraction is 35 and the number is 25.

fraction of number step 1

2

Divide the top number (called the numerator) of the fraction (3) by the bottom number (called the denominator) of the fraction (5).

fraction of number step 2
3 ÷ 5 = 0.6

3

Multiply the answer (0.6) by the number (25).

fraction of number step 3
0.6 × 25 = 15

Answer:

We have found 35 of 25.

fraction of number example answer

Lesson Slides

The slider below shows another real example of finding a fraction of a number.

Top Tip

Fraction of Number =
Fraction × Number

When you see a question like:
Find 12 of 10
Translate of into ×:
Find 12 × 10
of means times

Order of × and ÷ Doesn't Matter

In the example shown on this page, you:
  • find numerator ÷ denominator, then
  • × the number.
It is equally correct to do this the other way round:
  • find numerator × the number, then
  • ÷ by the denominator.