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Year 1 · Addition

Add within 20

Adding means putting two groups together. Past 10, it helps to make 10 first.

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How to do it

  1. Start with the bigger number.
  2. Count on to the next 10.
  3. Count on the rest.

Worked example

8 + 5
8 + 2 = 10, then 3 more.
8 + 5 = 13

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Break the smaller number so the first jump lands on 10.

Practise Add within 20 properly

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