Make ten, step by step
Ten is the number everything else is measured against.
The question
2 + ? = 10
■■□□□□□□□□
2+8=10
2 and 88 and 2
- Picture ten spaces in a row with 2 of them filled. The question is how many are still empty — not a sum to work out so much as a gap to see.
- Count the empty ones: 8. So 2 and 8 make 10.
- This pair is worth knowing by heart rather than counting each time — there are only five of them for ten, and 8 and 2 is the same pair the other way round. They are what makes 8 + 5 easy later: take 2 from the 5 to finish the ten.
How it works.
- 01
Picture ten spaces in a row with 2 of them filled. The question is how many are still empty — not a sum to work out so much as a gap to see.
- 02
Count the empty ones: 8. So 2 and 8 make 10.
- 03
This pair is worth knowing by heart rather than counting each time — there are only five of them for ten, and 8 and 2 is the same pair the other way round. They are what makes 8 + 5 easy later: take 2 from the 5 to finish the ten.