LCM( 75, 90, 125 ) = 2250
Step 1: Write down factorisation of each number:
75 = 3 · 5 · 5
90 = 2 · 3 · 3 · 5
125 = 5 · 5 · 5
Step 2 : Match primes vertically:
75 | = | 3 | · | 5 | · | 5 | ||||||
90 | = | 2 | · | 3 | · | 3 | · | 5 | ||||
125 | = | 5 | · | 5 | · | 5 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
75 | = | 3 | · | 5 | · | 5 | ||||||||
90 | = | 2 | · | 3 | · | 3 | · | 5 | ||||||
125 | = | 5 | · | 5 | · | 5 | ||||||||
LCM | = | 2 | · | 3 | · | 3 | · | 5 | · | 5 | · | 5 | = | 2250 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.