How do you find the least common multiple (LCM) of two numbers?

Finding the least common multiple (LCM) of two numbers involves identifying the smallest multiple that both numbers share. Option B accurately describes this process by suggesting that you list the multiples of both numbers and identify the smallest one that appears in both lists.

For example, if you want to find the LCM of 4 and 5, you would list the multiples of each: the multiples of 4 are 4, 8, 12, 16, 20, etc., and the multiples of 5 are 5, 10, 15, 20, 25, etc. The smallest number that appears in both lists is 20, which is the LCM.

This method is particularly useful for small numbers because it is straightforward and visual. However, for larger numbers, alternate methods, such as the one involving the greatest common factor (GCF), might be more efficient. But the direct approach described in option B remains a valid and fundamental method for understanding the concept of LCM.