LCM( 420, 360 ) = 2520
Step 1: Write down factorisation of each number:
420 = 2 · 2 · 3 · 5 · 7
360 = 2 · 2 · 2 · 3 · 3 · 5
Step 2 : Match primes vertically:
420 | = | 2 | · | 2 | · | 3 | · | 5 | · | 7 | ||||
360 | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | · | 5 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
420 | = | 2 | · | 2 | · | 3 | · | 5 | · | 7 | ||||||
360 | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | · | 5 | ||||
LCM | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | · | 5 | · | 7 | = | 2520 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.