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# 6. Least Common Multiple (LCM)

The least common multiple, or LCM, of numbers $$a$$ and $$b$$ is the smallest whole number $$m > 1$$ such that $$a$$ divides $$m$$ and $$b$$ divides $$m.$$

Example: Find the LCM of $$4$$ and $$6.$$

Solution $$\downarrow$$

To find the least common multiple of $$4$$ and $$6,$$ write a few multiples of each.
Multiples of $$4$$: $$4,$$ $$8,$$ $$12,$$ $$16,$$ $$20,$$ $$24,\dots$$
Multiples of $$6$$: $$6,$$ $$12,$$ $$18,$$ $$24,$$ $$30,\dots$$

If we compare both lists we can see that we have found two multiples in common, $$12$$ and $$24.$$ The LCM is $$12.$$

Find the LCM of these two numbers.