Find Least Common Multiple of 28 and 40 by listing out the factors.

LCM( 28, 40 ) = 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 40 are: 40, 80, 120, 160, 200, 240, 280, 320, . . .

We can see that:

LCM( 28, 40 ) = 280

This solution can be visualized using a Venn diagram.

The LCM is equal to the product of all the numbers on the diagram.