LCM( 40, 5, 27, 18 ) = 1080
Step 1: Write down factorisation of each number:
40 = 2 · 2 · 2 · 5
5 = 5
27 = 3 · 3 · 3
18 = 2 · 3 · 3
Step 2 : Match primes vertically:
40 | = | 2 | · | 2 | · | 2 | · | 5 | ||||||
5 | = | 5 | ||||||||||||
27 | = | 3 | · | 3 | · | 3 | ||||||||
18 | = | 2 | · | 3 | · | 3 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
40 | = | 2 | · | 2 | · | 2 | · | 5 | ||||||||
5 | = | 5 | ||||||||||||||
27 | = | 3 | · | 3 | · | 3 | ||||||||||
18 | = | 2 | · | 3 | · | 3 | ||||||||||
LCM | = | 2 | · | 2 | · | 2 | · | 3 | · | 3 | · | 3 | · | 5 | = | 1080 |