AngliaCampus[Advert]
 Search MathsAS/A2 Background Knowledge16-18 Post 16

Mathsnet logo online course
Curriculum materials for students, schools and colleges
created by MathsNet in partnership with AngliaCampus.
A B C D E
F G H I J
Further info
Tech 
A2. HCFs and LCMs : Least common multiple.

12 is a multiple of 3. 12 is also a multiple of 2. Therefore 2 and 3 have a common multiple of 12. The other common multiples, besides 12, of 2 and 3 are:
6, 18, 24, 30 and so on.
6 is the smallest in this list and is therefore called the least common multiple (LCM) of 2 and 3.

The least common multiple of 8 and 6 is 24.
The least common multiple of 12 and 10 is 60.

One way to work out the LCM of two numbers is to write each one as a product of their prime factors, and then pick out all the highest power of every factor mentioned.

8=2 x 2 x 2=23
20=2 x 2 x 5=22 x 51
The highest powers of factors=23 x 51=40, so 40 is the LCM of 8 and 20.

Find the LCM of two numbers yourself and check your answer. The correct answer is shown if you are wrong. Press the button to get started.



The LCM=

 blank blank Start Help + Feedback