Pairs of Numbers

If you have ten counters numbered 1 to 10, how many can you put into pairs that add to 10? Which ones do you have to leave out? Why?
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

Pairs of Numbers printable sheet

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Pairs of Numbers

 

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.