Stage 2 · The Four Operations & Estimation

2.4.4 Computing Cleverly with These Laws

2.4 The Laws of Operations: An Easier Way to Compute

Point 4 of 5

Core idea

Round to nice numbers and split things apart to lighten the work — for 25 × 4, make 100 first.

Module goal. Discover the commutative, associative, and distributive laws, and use them to rearrange expressions and speed up.

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