LCM (Lowest Common Multiple) - GCSE Maths Definition

Reviewed by: Dan Finlay

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The Lowest Common Multiple (LCM) is the smallest number that is a multiple of two or more given numbers. A multiple of a number is what you get when you multiply that number by a whole number.

For example, if you have the numbers 4 and 6, the multiples of 4 are 4, 8, 12, 16, and so on, while the multiples of 6 are 6, 12, 18, 24, and so on. The LCM of 4 and 6 is 12 because it is the smallest number that appears in both lists of multiples.

Finding the LCM is useful when solving problems involving adding or subtracting fractions with different denominators or finding common cycles.

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Dan Finlay

Reviewer: Dan Finlay

Expertise: Maths Subject Lead

Dan graduated from the University of Oxford with a First class degree in mathematics. As well as teaching maths for over 8 years, Dan has marked a range of exams for Edexcel, tutored students and taught A Level Accounting. Dan has a keen interest in statistics and probability and their real-life applications.

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