LCM( 225, 440, 660 ) = 19800
Step 1: Write down factorisation of each number:
225 = 3 · 3 · 5 · 5
440 = 2 · 2 · 2 · 5 · 11
660 = 2 · 2 · 3 · 5 · 11
Step 2 : Match primes vertically:
225 | = | 3 | · | 3 | · | 5 | · | 5 | ||||||||
440 | = | 2 | · | 2 | · | 2 | · | 5 | · | 11 | ||||||
660 | = | 2 | · | 2 | · | 3 | · | 5 | · | 11 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
225 | = | 3 | · | 3 | · | 5 | · | 5 | ||||||||||
440 | = | 2 | · | 2 | · | 2 | · | 5 | · | 11 | ||||||||
660 | = | 2 | · | 2 | · | 3 | · | 5 | · | 11 | ||||||||
LCM | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | · | 5 | · | 5 | · | 11 | = | 19800 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.