LCM( 18, 29, 21 ) = 3654
Step 1: Write down factorisation of each number:
18 = 2 · 3 · 3
29 = 29
21 = 3 · 7
Step 2 : Match primes vertically:
18 | = | 2 | · | 3 | · | 3 | ||||
29 | = | 29 | ||||||||
21 | = | 3 | · | 7 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
18 | = | 2 | · | 3 | · | 3 | ||||||
29 | = | 29 | ||||||||||
21 | = | 3 | · | 7 | ||||||||
LCM | = | 2 | · | 3 | · | 3 | · | 7 | · | 29 | = | 3654 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.