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Greatest common factor

The biggest number that divides two numbers exactly. 12 biscuits and 18 sweets make at most 6 equal party bags, because 6 is the biggest number in both lists of factors (12 = 2 × 2 × 3 and 18 = 2 × 3 × 3 share 2 × 3). Also called the highest common factor.

Depth 1 · Foundation

You can find the common factors of two numbers and the greatest of them, use it for "as many equal groups as possible" and the biggest square tile, and know that some pairs share only 1.

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Depths of understanding

  1. 1

    Foundation

    You can find the common factors of two numbers and the greatest of them, use it for "as many equal groups as possible" and the biggest square tile, and know that some pairs share only 1.

    Opens after

    FactorsA common factor is a number in both lists of factors, so you need to find each number's factors first.

Your path here

What's still between you and Greatest common factor, depth 1, in the order you can learn it.

  1. 1CountingDepth 1 · Foundation · Number Systems
  2. 2Natural numbersDepth 1 · Foundation · Number Systems
  3. 3ZeroDepth 1 · Foundation · Number Systems
  4. 4The number lineDepth 1 · Foundation · Number Systems
  5. 5AdditionDepth 1 · Foundation · Arithmetic
  6. 6MultiplicationDepth 1 · Foundation · Arithmetic
  7. 7MultiplesDepth 1 · Foundation · Number Theory
  8. 8FactorsDepth 1 · Foundation · Number Theory
  9. 9Greatest common factorDepth 1 · Foundation · Number Theory

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