63, 126, 189, 252, 315 . . .
The common multiples of 9 and 21 are 63, 126, 189 and so on.
If that's 9, 14 and 21, the first three common multiples are 126, 252 and 378.
63, 126, 189
Any pair of numbers has an infinite set of common multiples. The lowest common multiple of 9 and 21 is 63 and the others are multiples of this, e.g. 63, 126, 189, 252, 315, ...
126, 252, 378
63, 126, 189
126, 252, 378 and so on.
The first three multiples of 3 are 3, 6, 9 The first three multiples of 9 are 9, 18, 27 As the lowest common multiples of 3 and 9 is 9, the common multiples of 3 and 9 are the multiples of 9, thus: The first three common multiples of 3 and 9 are 9, 18, 27
LCM(9, 21) = 63 so the numbers are 63, 63*2 and 63*3.
They are: 63, 126, 189, 252, 315, 378.
Common multiples are multiples that are common to two or more numbers.9: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108, 117, 126, 135, 144, 153, 162, 171, 180, 18921: 21, 42, 63, 84, 105, 126, 147, 168, 189The first 3 common multiples of 9 and 21 are 63, 126 and 189.63, 126, 189.
126