# Mental addition and subtraction (age 6+)

Add and subtract a two-digit number and ones mentally and using concrete/pictorial representations

Builds on: Adding and subtracting (hard, https://ai.page/c/adding-and-subtracting/en.md), The two digits of a two-digit number (hard, https://ai.page/c/the-two-digits-of-a-two-digit-number/en.md)

Concept id: mental-addition-and-subtraction-age-6. Subject: maths. Licence: CC BY-SA 4.0.

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