LCM( 20, 25, 35, 50 ) = 700
Step 1: Write down factorisation of each number:
20 = 2 · 2 · 5
25 = 5 · 5
35 = 5 · 7
50 = 2 · 5 · 5
Step 2 : Match primes vertically:
20 | = | 2 | · | 2 | · | 5 | ||||
25 | = | 5 | · | 5 | ||||||
35 | = | 5 | · | 7 | ||||||
50 | = | 2 | · | 5 | · | 5 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
20 | = | 2 | · | 2 | · | 5 | ||||||
25 | = | 5 | · | 5 | ||||||||
35 | = | 5 | · | 7 | ||||||||
50 | = | 2 | · | 5 | · | 5 | ||||||
LCM | = | 2 | · | 2 | · | 5 | · | 5 | · | 7 | = | 700 |