LCM( 4, 6, 2, 15 ) = 60
Step 1: Write down factorisation of each number:
4 = 2 · 2
6 = 2 · 3
2 = 2
15 = 3 · 5
Step 2 : Match primes vertically:
4 | = | 2 | · | 2 | ||||
6 | = | 2 | · | 3 | ||||
2 | = | 2 | ||||||
15 | = | 3 | · | 5 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
4 | = | 2 | · | 2 | ||||||
6 | = | 2 | · | 3 | ||||||
2 | = | 2 | ||||||||
15 | = | 3 | · | 5 | ||||||
LCM | = | 2 | · | 2 | · | 3 | · | 5 | = | 60 |