Number bonds to 100 | Year 3 Mathematics PDF Download

How can we show the number bonds to 10?

There are various ways to display bonds to 10. For instance, we can use a bonds to ten rainbow, like this.

We can use 10 frames, like this.

When you have mastered your number bonds to 10, you can rely on known number facts to quickly determine new ones.
For instance:

• 1 + 9 = 10
• 2 + 8 = 10
• 3 + 7 = 10
• 4 + 6 = 10
• 5 + 5 = 10

You can use these number facts to work out new ones.

Solved Examples

Example 1: What must I add to 37 to make 100?
Let’s use a part whole model to show this.
First, let’s make 37 and partition it into tens and ones.

How many do you need to add to 7 to make another multiple of 10?
You need 3, so let’s draw another part-whole model and write in 3.

30 + 7 + 3 makes 40.
What do you need to add to 40 to make 100?
You will need 60.

What number do we write in the top part of the part whole model?
3 + 60 = 63

Now add up all the multiples of 10.
This shows that:
37 + 63 = 100

Another way to solve this would be to subtract 37 from 100.
Look at this 100 square, where 37 has been taken away from 100.
The answer is 63.
100 - 37 = 63

Example 2: Here is the number 2.
Here is 2 made 10 times bigger. How many can you see now?
2 multiplied by 10 equals 20.

Example 3: Let's see if this works for other numbers.
We know that 6 + 4 = 10, does that mean 60 + 40 = 100?
Let's look at the 100 square to check.

Can you see how the total is 100? 40 blocks are white and 60 blocks are yellow.
There are 100 blocks altogether.
40 + 60 = 100
Have a look at the number line below to see the same sum.