What is the least common factor of 5 and 15?

To answer the question, "What is the least common factor of 5 and 15?", we will start by defining and listing factors of 5 and 15.

Factors of 5 are all the integers that when multiplied by another integer equal 5. Likewise, factors of 15 are all the integers that when multiplied by another integer equal 15.

The factors of 5 are 1 and 5.

The factors 15 are 1, 3, 5, and 15.

When you ask, "What is the least common factor of 5 and 15?", least is the key word here. Least means smallest. Thus, the smallest or least common factor that 5 and 15 have in common is 1.

Note that all integers, such as 5 and 15, 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 5 and 15, you may also be interested in knowing the greatest common factor of 5 and 15. The greatest factor 5 and 15 have in common, per the list above, is 5.

When you asked for the least common factor of 5 and 15, did you mean least common multiple? If so, the least common multiple of 5 and 15 is 15.

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