
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.