NumberPuzzle

Four Fours:Product of prime factors

Sixteen products sorted into 60, 90, 72 and 84: each number as a product of primes, in index form and as a factor pair. 2² × 3 × 5 and 2 × 3² × 5 look alike and are not. Two per A4.

A free key stage 3 and GCSE number puzzle with answers, spec code N4. It goes with the lesson on prime factor decomposition.

Puzzle

Four Fours:Product of prime factors

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Prime factor decompositionThe Maths Habit

Lesson

Prime factor decomposition

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