GCSE · Integers, powers & roots

HCF and LCMExam-style questions

What highest common factor and lowest common multiple actually mean, how prime factors give both (lowest powers vs highest powers), and how to spot which one a word problem is asking for.

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14 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 1Level 2Level 3Level 4Level 5
  1. 1
    Two whole numbers are each greater than 6.

    The highest common factor of the two numbers is 6.

    The lowest common multiple of the two numbers is 90.

    Find the two numbers.
    Level 5 · 3 marksTry it
  2. 2
    The highest common factor of two numbers is 44.

    The lowest common multiple of the same two numbers is 4848.

    One of the numbers is 1212.

    Find the other number.
    Level 5 · 3 marksTry it