Find Least Common Multiple of 7, 3 and 4 using prime factorisation method.
Answer
LCM( 7, 3, 4 ) = 84
Explanation
Step 1: Write down factorisation of each number:
7 = 7
3 = 3
4 = 2 · 2
Step 2 : Match primes vertically:
| 7 | = | 7 | ||||||
| 3 | = | 3 | ||||||
| 4 | = | 2 | · | 2 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
| 7 | = | 7 | ||||||||
| 3 | = | 3 | ||||||||
| 4 | = | 2 | · | 2 | ||||||
| LCM | = | 2 | · | 2 | · | 3 | · | 7 | = | 84 |
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