6.13 Multiplication by 5

Can you count up by fives? Let's practice now. Continue this pattern: 5,\,10,\,15,\,20\,...

What you may not have realised is that when you're counting up with this pattern, you are actually looking at multiples of five and saying the answers to your five times tables.

Similar to how we can use a doubling strategy for our 2,4 and 8 times tables, we can use a halving strategy for our 5 times tables because half of 10 groups is 5 groups. Watch this video to see how.

Examples

Example 1

Find the product of 5\times 6.

Worked Solution

Create a strategy

We can think of 5\times 6 as 5 groups of 6 just like in the image below which has 5 groups of 6 squares:

Apply the idea

The image above has 30 squares in total.5\times 6 = 30

Reflect and check

Or we can use the halving strategy by first finding 10 \times 6 and halving the answer.

\displaystyle 10 \times 6	\displaystyle =	\displaystyle 60	Move 6 to the tens and add a 0
\displaystyle 5 \times 6	\displaystyle =	\displaystyle 30	Find half of 60

Watch question walkthrough