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?

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Problem

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?

Why or why not?
 

Now put the counters into pairs to make 12.

  • Can you use them all?
  • Why or why not?

Now put the counters into pairs to make 13.

  • Can you use them all?
  • Why or why not?

Now put the counters into pairs to make 11.

  • Can you use them all?
  • Why or why not?