Multiplication shortcuts (distributive law)
An expression that looks like hard work, such as 749 × 215 + 215 × 9251. Both parts share a number, so it can be rewritten as 215 × (749 + 9251) = 215 × 10,000.
Half the questions add and half subtract, and the pair always makes a power of ten, so spotting the shortcut turns it into easy mental maths.
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What changes each time
- Addition and subtraction forms
- Pairs that make 10, 100, 1,000 or 10,000
- A new expression every time
More algebra and order of operations practice
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