# Adding and subtracting (age 9+)

Solve addition and subtraction multi-step problems in contexts, deciding which operations and methods to use and why

Builds on: Two-step addition and subtraction problems (hard, https://ai.page/c/two-step-addition-and-subtraction-problems/en.md), Mental addition and subtraction (age 9+) (soft, https://ai.page/c/mental-addition-and-subtraction-age-9/en.md), Fluent addition and subtraction (age 9+) (hard, https://ai.page/c/fluent-addition-and-subtraction-age-9/en.md)

Concept id: adding-and-subtracting-age-9. Subject: maths. Licence: CC BY-SA 4.0.

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