The traffic lights at three different road crossings change after every 48 sec., 72 sec and 108 sec. respectively .If they all change simultaneously at 8:20:00 hours, then at what time they again change simultaneously .  Options.
A) 8:27:12
B) 8:25:12
C) 8:26:12
D) 8:24:12
E) None of them
Interval of change = (L.C.M of 48,72,108)sec.=432sec.   So, the lights will agin change simultaneously after every 432 seconds i.e,7 min.12sec   Hence , next simultaneous change will take place at 8:27:12 hrs.   8:27:12nswer is 8:27:12.
<result>A</result>
The traffic lights at three different road crossings change after every 48 sec., 72 sec and 108 sec. respectively .If they all change simultaneously at 8:20:00 hours, then at what time they again change simultaneously .