LCM( 28, 56, 70 ) = 280
Write down multiples of each number until you find the first common multiple:
The multipliers of 28 are: 28, 56, 84, 112, 140, 168, 196, 224, 252, 280, 308, . . .
The multipliers of 56 are: 56, 112, 168, 224, 280, 336, . . .
The multipliers of 70 are: 70, 140, 210, 280, 350, . . .
We can see that:
LCM( 28, 56, 70 ) = 280
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.