LCM( 54, 72, 100 ) = 5400
Write down multiples of each number until you find the first common multiple:
The multipliers of 54 are:
The multipliers of 72 are: 72, 144, 216, 288, 360, 432, 504, 576, 648, 720, 792, 864, 936, 1008, 1080, 1152, 1224, 1296, 1368, 1440, 1512, 1584, 1656, 1728, 1800, 1872, 1944, 2016, 2088, 2160, 2232, 2304, 2376, 2448, 2520, 2592, 2664, 2736, 2808, 2880, 2952, 3024, 3096, 3168, 3240, 3312, 3384, 3456, 3528, 3600, 3672, 3744, 3816, 3888, 3960, 4032, 4104, 4176, 4248, 4320, 4392, 4464, 4536, 4608, 4680, 4752, 4824, 4896, 4968, 5040, 5112, 5184, 5256, 5328, 5400, 5472, . . .
The multipliers of 100 are: 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300, 3400, 3500, 3600, 3700, 3800, 3900, 4000, 4100, 4200, 4300, 4400, 4500, 4600, 4700, 4800, 4900, 5000, 5100, 5200, 5300, 5400, 5500, . . .
We can see that:
LCM( 54, 72, 100 ) = 5400
This solution can be visualized using a Venn diagram.
The LCM is equal to the product of all the numbers on the diagram.