63, 126 and 189
If that's 9, 14 and 21, the first three common multiples are 126, 252 and 378.
63, 126, 189
63, 126, 189
126, 252, 378
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
They are the first three multiples of LCM(5, 9), that is, the first three multiples of 45.
126, 252, 378 and so on.
LCM(9, 21) = 63 so the numbers are 63, 63*2 and 63*3.
3, 6, 9, 12, 15, 18, 21, 24.
3,6,9,12,15,18,21,24,27,30 and so on but these are the first ten multiples of three
3, 6, 9, 12, 15, 18, 21.
The first three multiples of 9 are 9, 18 and 27. For them to be common, they need to be compared to another set of factors.