LCM( 28, 30, 36 ) = 1260
Step 1: Write down factorisation of each number:
28 = 2 · 2 · 7
30 = 2 · 3 · 5
36 = 2 · 2 · 3 · 3
Step 2 : Match primes vertically:
28 | = | 2 | · | 2 | · | 7 | ||||||
30 | = | 2 | · | 3 | · | 5 | ||||||
36 | = | 2 | · | 2 | · | 3 | · | 3 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
28 | = | 2 | · | 2 | · | 7 | ||||||||
30 | = | 2 | · | 3 | · | 5 | ||||||||
36 | = | 2 | · | 2 | · | 3 | · | 3 | ||||||
LCM | = | 2 | · | 2 | · | 3 | · | 3 | · | 5 | · | 7 | = | 1260 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.