Question

The traffic lights at three different road crossing change after every 36 sec,60 sec,72sec. If the change simultaneously at 8 a.m. after,what time will they change again simultaneously ?

Answer 1

This question is based on the concept of LCM.

So, the LCM of 36,60 and 72=120

So, that means that after 120 seconds (2 minutes) the lights will change again= At 8:02 a.m.