Copyright © University of Cambridge. All rights reserved.

## 'Pairs of Numbers' printed from http://nrich.maths.org/

### Show menu

If you have ten counters numbered $1$ to $10$, how many can you put into pairs that add to $10$?

Can you use them all?
Say how you got your answer.

Now put the counters into pairs to make $12$.
• Can you use them all?
• Say how you got your answer.
Now put the counters into pairs to make $13$.
• Can you use them all?
• Say how you got your answer.

Now put the counters into pairs to make $11$.
• Can you use them all?
• Say how you got your answer.