Find Least Common Multiple of 10, 21 and 35 using prime factorisation method.
Answer
LCM( 10, 21, 35 ) = 210
Explanation
Step 1: Write down factorisation of each number:
10 = 2 · 5
21 = 3 · 7
35 = 5 · 7
Step 2 : Match primes vertically:
| 10 | = | 2 | · | 5 | ||||
| 21 | = | 3 | · | 7 | ||||
| 35 | = | 5 | · | 7 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
| 10 | = | 2 | · | 5 | ||||||
| 21 | = | 3 | · | 7 | ||||||
| 35 | = | 5 | · | 7 | ||||||
| LCM | = | 2 | · | 3 | · | 5 | · | 7 | = | 210 |
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