7 of course
If you mean the 'least' or 'smallest' common multiple of 9 and 8, then 288 is.
it would be 81 since it is a multiple of 9
10, 36 and 900
36
108
0 isn't the first multiple of 9.
They are: 9, 18 and 27
45
288. All multiples of 9 will have digits that add to a multiple of 9. To get a multiple of 9 to be all even, you need to get them to add to 18, since no set of even numbers will add up to 9. 288 is the lowest multiple of 9 to be able to add to 18. ■
LCM(6, 7, 9) = 126.
45 9, 18, 27, 36, 45... 45 is the first multiple of 9 that is divisible by 5.