Question: which is not a common multiple of 3 and 8?
Answer: Lowest Common Multiple. The smallest common multiple of two or more numbers is called the lowest common multiple (LCM). E.g. Multiples of 8 are 8, 16, 24, 32, … Multiples of 3 are 3, 6, 9, 12, 15, 18, 21, 24, …