Find Least Common Multiple of 81 and 108 using prime factorisation method.
Answer
LCM( 81, 108 ) = 324
Explanation
Step 1: Write down factorisation of each number:
81 = 3 · 3 · 3 · 3
108 = 2 · 2 · 3 · 3 · 3
Step 2 : Match primes vertically:
| 81 | = | 3 | · | 3 | · | 3 | · | 3 | ||||
| 108 | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
| 81 | = | 3 | · | 3 | · | 3 | · | 3 | ||||||
| 108 | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 | ||||
| LCM | = | 2 | · | 2 | · | 3 | · | 3 | · | 3 | · | 3 | = | 324 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.
This page was created using
LCM Calculator