What is the least common factor of 20 and 40?

To answer the question, "What is the least common factor of 20 and 40?", we will start by defining and listing factors of 20 and 40.

Factors of 20 are all the integers that when multiplied by another integer equal 20. Likewise, factors of 40 are all the integers that when multiplied by another integer equal 40.

The factors of 20 are 1, 2, 4, 5, 10, and 20.

The factors 40 are 1, 2, 4, 5, 8, 10, 20, and 40.

When you ask, "What is the least common factor of 20 and 40?", least is the key word here. Least means smallest. Thus, the smallest or least common factor that 20 and 40 have in common is 1.

Note that all integers, such as 20 and 40, have 1 as one of its factors. Thus, the answer to the least common factor of any two integers greater than 0 will always be 1.

Now that you know the least common factor of 20 and 40, you may also be interested in knowing the greatest common factor of 20 and 40. The greatest factor 20 and 40 have in common, per the list above, is 20.

When you asked for the least common factor of 20 and 40, did you mean least common multiple? If so, the least common multiple of 20 and 40 is 40.

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