LCM( 10, 16, 40 ) = 80
Step 1: Write down factorisation of each number:
10 = 2 · 5
16 = 2 · 2 · 2 · 2
40 = 2 · 2 · 2 · 5
Step 2 : Match primes vertically:
10 | = | 2 | · | 5 | ||||||
16 | = | 2 | · | 2 | · | 2 | · | 2 | ||
40 | = | 2 | · | 2 | · | 2 | · | 5 |
Step 3 : Bring down numbers in each column and multiply to get LCM:
10 | = | 2 | · | 5 | ||||||||
16 | = | 2 | · | 2 | · | 2 | · | 2 | ||||
40 | = | 2 | · | 2 | · | 2 | · | 5 | ||||
LCM | = | 2 | · | 2 | · | 2 | · | 2 | · | 5 | = | 80 |
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.