Find Least Common Multiple of 68 and 70 by listing out the factors.

LCM( 68, 70 ) = 2380

Write down multiples of each number until you find the first common multiple:

The multipliers of 68 are: 68, 136, 204, 272, 340, 408, 476, 544, 612, 680, 748, 816, 884, 952, 1020, 1088, 1156, 1224, 1292, 1360, 1428, 1496, 1564, 1632, 1700, 1768, 1836, 1904, 1972, 2040, 2108, 2176, 2244, 2312, 2380, 2448, . . .

The multipliers of 70 are: 70, 140, 210, 280, 350, 420, 490, 560, 630, 700, 770, 840, 910, 980, 1050, 1120, 1190, 1260, 1330, 1400, 1470, 1540, 1610, 1680, 1750, 1820, 1890, 1960, 2030, 2100, 2170, 2240, 2310, 2380, 2450, . . .

We can see that:

LCM( 68, 70 ) = 2380

This solution can be visualized using a Venn diagram.

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