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Least common multiple
Least common multiple 256
Description
Exercise Name: Least common multiple
Math Missions: 6th grade (U.S.) Math Mission, Pre-algebra Math Mission, Mathematics I Math Mission
Types of Problems: 1

The Least common multiple exercise appears under the 6th grade (U.S.) Math Mission, Pre-algebra Math Mission and Mathematics I Math Mission. This exercise provides experience and practice with calculating the least common multiple of two numbers.

Types of Problems[]

There is one type of problem in this exercise:

  1. Find the least common multiple: This problem provides two numbers and asks the user to find and write the least common multiple of those two numbers.
    Lcm1

    Find the least common multiple

Strategies[]

This exercise is medium to get accuracy badges because there are many bad habits the can arise when doing least common multiples. As long as the bad habits are avoided, the speed badges should be considered easy.

  1. Least common multiple is often abbreviated by LCM.
  2. The bad habit with least common multiple is multiplying the two numbers, which is a common multiple but not necessarily the least common multiple.
  3. The best habit is to break numbers into their prime factorization and select the common factors to create the least common multiple. This, however, is not fast.
  4. Some fast techniques are to mentally compute multiple of one number until students reach a multiple of the other number.

Real-life Applications[]

  1. Hot dogs and buns are an example of GCF and LCM in real life. For example, LCM can be used to solve this problem: "Hot dogs come in packages of 10, while rolls come in either 8 or 12. What's the smallest number of each they have to buy to have the same number of each?"