List the multiples of 9 and the multiples of 12. What is the first number to appear on both lists?

1. List multiples of 9: 9, 18, 27, 36, 45, and so on. 2. List multiples of 12: 12, 24, 36, 48, and so on. 3. The smallest number on both lists is 36, so the least common multiple of 9 and 12 is 36. 4. 72 and 108 sit on both lists too, but they are larger than 36, so they are common multiples without being the least. _Source: OpenStax Elementary Algebra (CC BY 4.0), Ch 1 "Foundations", section 1.1 Introduction to Whole Numbers_