LCM( 12, 140 ) = 420
Step 1: Write down factorisation of each number:
12 = 2 · 2 · 3
140 = 2 · 2 · 5 · 7
Step 2 : Match primes vertically:
12 | = | 2 | · | 2 | · | 3 | ||||
140 | = | 2 | · | 2 | · | 5 | · | 7 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
12 | = | 2 | · | 2 | · | 3 | ||||||
140 | = | 2 | · | 2 | · | 5 | · | 7 | ||||
LCM | = | 2 | · | 2 | · | 3 | · | 5 | · | 7 | = | 420 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.