Question
Find Least Common Multiple of 25, 50, 75, 100, 125 and 150 using prime factorisation method.
Answer
LCM( 25, 50, 75, 100, 125, 150 ) = 1500
Explanation
Step 1: Write down factorisation of each number:
25 = 5 · 5
50 = 2 · 5 · 5
75 = 3 · 5 · 5
100 = 2 · 2 · 5 · 5
125 = 5 · 5 · 5
150 = 2 · 3 · 5 · 5
Step 2 : Match primes vertically:
| 25 | = | 5 | · | 5 | ||||||||
| 50 | = | 2 | · | 5 | · | 5 | ||||||
| 75 | = | 3 | · | 5 | · | 5 | ||||||
| 100 | = | 2 | · | 2 | · | 5 | · | 5 | ||||
| 125 | = | 5 | · | 5 | · | 5 | ||||||
| 150 | = | 2 | · | 3 | · | 5 | · | 5 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
| 25 | = | 5 | · | 5 | ||||||||||
| 50 | = | 2 | · | 5 | · | 5 | ||||||||
| 75 | = | 3 | · | 5 | · | 5 | ||||||||
| 100 | = | 2 | · | 2 | · | 5 | · | 5 | ||||||
| 125 | = | 5 | · | 5 | · | 5 | ||||||||
| 150 | = | 2 | · | 3 | · | 5 | · | 5 | ||||||
| LCM | = | 2 | · | 2 | · | 3 | · | 5 | · | 5 | · | 5 | = | 1500 |
This page was created using
LCM Calculator