Fractions of Whole Numbers | Year 6 Maths | KS2 Resources

## What you need to know

Things to remember:

• To find the fraction of a number or amount of something, we divide by the denominator and then multiply by the numerator.

Let’s think about what fractions are. Imagine we have a block.

And we cut this block in half.

What did we do? We divided it into two pieces. So, to find $\dfrac{1}{2}$ we divide by 4.

How about if we cut the block into quarters?

What did we do? We divided it into four pieces. So, to find $\dfrac{1}{4}$ we divide by 4.

How about if we cut the block into fifths?

What did we do? We divided it into five pieces. So, to find $\dfrac{1}{5}$ we divide by 5.

Notice how we just divide by the denominator when we are looking for a fraction amount of something and there is a 1 on top of the fraction.

What is $\dfrac{1}{5}$ of 20?

$\dfrac{1}{5}$ of 20 = $20\div5=4$

What is $\dfrac{1}{12}$ of 72?

$\dfrac{1}{12}$ of 72 = $72\div12=6$

But, how about if we want to find something like $\frac{3}{5}$ of 20? We have previously seen how to multiply fractions and whole numbers, so we can actually write $\dfrac{3}{5}$.

$$\frac{3}{5}=3\times\frac{1}{5}$$

So really, this is asking us to find 3 lots of $\dfrac{1}{5}$ of 20.

$\dfrac{1}{5}$ of 20 = $20\div5=4$

$$3\times4=12$$

$\dfrac{3}{5}$ of 20 = 12

This gives us the two steps we need for finding fraction amounts.

What is $\dfrac{6}{7}$ of 21?

Step 1: Divide the amount by the denominator.

$$21\div7=3$$

Step 2: Multiply the number in Step 1 by the numerator.

$$3\times6=18$$

$\dfrac{6}{7}$ of 21 = 18

## KS2 SATs Flash Cards

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## Example Questions

Step 1: Divide the amount by the denominator.

$$63\div9=7$$

Step 2: Multiply the number in Step 1 by the numerator.

$$7\times5=35$$

$\dfrac{5}{9}$ of 63 = 35

Step 1: Divide the amount by the denominator.

$$88\div11=8$$

Step 2: Multiply the number in Step 1 by the numerator.

$$3\times8=24$$

$$\frac{3}{11}$$ of 88 = 24

## Times Table Flash Cards

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• All of the KS2 times tables are covered
• Engaging and fun maths cards