LCM( 175, 420, 420 ) = 2100
Step 1: Write down factorisation of each number:
175 = 5 · 5 · 7
420 = 2 · 2 · 3 · 5 · 7
420 = 2 · 2 · 3 · 5 · 7
Step 2 : Match primes vertically:
175 | = | 5 | · | 5 | · | 7 | ||||||
420 | = | 2 | · | 2 | · | 3 | · | 5 | · | 7 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
175 | = | 5 | · | 5 | · | 7 | ||||||||
420 | = | 2 | · | 2 | · | 3 | · | 5 | · | 7 | ||||
LCM | = | 2 | · | 2 | · | 3 | · | 5 | · | 5 | · | 7 | = | 2100 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.