LCM( 72, 108 ) = 216
Step 1: Write down factorisation of each number:
72 = 2 · 2 · 2 · 3 · 3
108 = 2 · 2 · 3 · 3 · 3
Step 2 : Match primes vertically:
72 | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | ||
108 | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
72 | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | ||||
108 | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 | ||||
LCM | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | · | 3 | = | 216 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.