Fraction of an amount

Hello, and welcome to Myriora Maths! There are forty sweets in a jar, and you can have three fifths of them. How many is that? Let's find out how to work out a fraction of an amount.

Let's start with one quarter of twenty. One quarter means: share into four equal groups. Twenty counters in four groups is five in each group. So one quarter of twenty is five.

Three quarters of twenty is three of those groups. Three times five is fifteen. So three quarters of twenty is fifteen.

So here's the method. Divide by the bottom, then multiply by the top. Three fifths of forty: forty divided by five is eight. Eight times three is twenty-four!

It works with money too. Two thirds of twenty-four pounds: twenty-four divided by three is eight pounds. Eight times two is sixteen pounds.

Let's try one together. What is two thirds of eighteen? Say it out loud!

Eighteen divided by three is six. Six times two is twelve!

Here's a question that catches lots of people. What is three fifths of forty? Some people divide by three, because the three comes first. But the bottom number tells you how many equal parts, so divide by five first! Forty divided by five is eight, and eight times three is twenty-four.

Your turn! What is two fifths of thirty-five? Pick the right card. You've got twenty seconds, or pause the video. Go!

Time's up! Thirty-five divided by five is seven. Seven times two is fourteen!

Quick review. One quarter of an amount means sharing it into four equal groups. To find a fraction of an amount, divide by the bottom, then multiply by the top. A bar cut into equal parts helps you see it. And always divide by the bottom number first! See you next time!