Least common multiple (LCM)
Greatest common factor (GCF)
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Work out the LCM (least common multiple) of two numbers.
What is the least common multiple of 12 and 18?
This exercise finds the least common multiple (LCM) of two numbers — the smallest number that both of them divide into exactly. You will use the LCM later as a common denominator when adding fractions with different denominators.
What does this generator do?
Picks two numbers from a friendly range (4 to 48). You look for the smallest number that both will divide into exactly.
How to use it
Easiest formula: LCM(a, b) = (a × b) / GCF(a, b). Or list multiples of the larger number until you find one the smaller number divides into.
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