Ctrl+k

Find the least common multiple

The least common multiple (LCM) of two or more positive whole numbers is the smallest positive number that is a multiple of each, identifying the first shared value in their patterns of multiples. It may be found by listing multiples or by using prime factorizations, taking each prime factor with its greatest exponent; it is distinct from the greatest common factor and is not generally the product of the numbers. This scope focuses on manageable whole numbers and common-denominator or repeating-cycle applications, not advanced generalized treatments.

Detailed Explanation: Find the least common multiple

The least common multiple (LCM) is the smallest positive number that is a multiple of two or more numbers.

To find it, list the multiples of each number until you find the first number that appears in every list.

Example: Find the LCM of 66 and 88.

  1. List multiples of 66:

6, 12, 18, 24, 30, 36,6,\ 12,\ 18,\ 24,\ 30,\ 36,\dots
  1. List multiples of 88:

8, 16, 24, 32, 40,8,\ 16,\ 24,\ 32,\ 40,\dots
  1. Find the first number that appears in both lists. The first shared number is 2424.

Therefore,

LCM(6,8)=24\boxed{\operatorname{LCM}(6,8)=24}

Check: 2424 is a multiple of both numbers because 6×4=246\times4=24 and 8×3=248\times3=24. Since no smaller positive number appears in both lists, 2424 is the least common multiple.

Learn by doing: Find the least common multiple

Click a topic below to practice the foundational skills you'll need, learn the steps, or master this skill

Practice with unlimited practice problems

Finding Lowest Common Multiple


    ?