18
The LCM of 2 and 9 is 18
2
6
The three LCMs pf 2,3 & 6 are 6, 12 & 18
The LCM of 315 and 9 is 315
36
42
The LCM of 9 and 13 is 117.
Good old LCMs! 1/6 = 5/30, 3/10 = 9/30 so the answer is -4/30 ie -2/15
36 and 3, respectively.
The first 6 common multiples are: 60, 120, 180, 240, 300, 360.
The LCMs of 5 and 9 is 45