LCM( 9, 30, 108 ) = 540
Step 1: Write down factorisation of each number:
9 = 3 · 3
30 = 2 · 3 · 5
108 = 2 · 2 · 3 · 3 · 3
Step 2 : Match primes vertically:
9 | = | 3 | · | 3 | ||||||||
30 | = | 2 | · | 3 | · | 5 | ||||||
108 | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
9 | = | 3 | · | 3 | ||||||||||
30 | = | 2 | · | 3 | · | 5 | ||||||||
108 | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 | ||||
LCM | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 | · | 5 | = | 540 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.