On a road three consecutive traffic lights change after 36, 42 and 72 seconds respectively. If the lights are first switched on at 9:00 AM sharp, at what time will they change simultaneously?

On a road three consecutive traffic lights change after 36, 42 and 72

1.	On a road three consecutive traffic lights change after 36, 42 and 72 seconds respectively. If the lights are first switched on at 9:00 AM sharp, at what time will they change simultaneously?
A.	9:08:04
B.	9:08:24
C.	9:08:44
D.	None of these
Answer» C. 9:08:44