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KeyStage 2 Upper

Complete factor expressions (below 100)


We can make any number by using its factor pairs. Every number will have at least one factor pair, $1$1 and itself. 

When we're completing factor expressions we need to think of a second number we can use to complete an expression. We can do this by counting or maybe dividing. Let's look at an example...

Complete the factor expression below


Here we need to complete the factor expression by finding what goes in the $\editable{}$.

So far we know two numbers $7$7 and $21$21. We can use these two numbers to work out the missing number. 
We can either find the result of $21\div7$21÷​7 or we can count by $7$7's.

If we count by $7$7's we get...

$7$7, $14$14, $21$21

On a number line it would look like this...

We can now see that we'll have to count by $7$7 three times before we get to $21$21, so $3$3 groups of $7$7 make $21$21

So, the number $3$3 completes the factor expression. 


We can use the multiplication tables to help us work out factors of a number.


Use the sliders below to find that factor pair.  


Question 1

Fill in the box with the missing number.

  1. $6\times\editable{}=60$6×=60

Question 2

Fill in the box with the missing number.

  1. $11\times\editable{}=22$11×=22

Question 3

Fill in the gaps to find all factor pairs of $66$66.

  1. $1,\editable{}$1,




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