Home/Sixth Grade Math/Week 1: Factors and multiples/Lesson 6

Least Common Multiple

The least common multiple (LCM) is the smallest number two or more numbers can both divide into.

Lesson 6

Concept

LCM helps when finding common denominators and scheduling repeated events. Method 1: List multiples - Multiples of 6: 6, 12, 18, 24, 30... - Multiples of 8: 8, 16, 24, 32... First common multiple is 24, so LCM(6,8)=24. Method 2: Prime factors - 12 = 2 x 2 x 3 - 18 = 2 x 3 x 3 Take highest powers: 2 x 2 x 3 x 3 = 36 So LCM(12,18)=36.

Try it

Practice: Least Common Multiple.