Question

The traffic lights at three different road crossings change after every 48 seconds, 72
seconds and 108 seconds respectively. If they all change simultaneously at 8:20:00 am
when will all the traffic lights again change simultaneously?​

Answer 1

Answer:

First of all we have find the LCM of all timing

LCM (48,72,108) = 432 seconds

432 sec = 7 min 12 seconds

Next time of traffic light change is

8:20:00 a.m + 7 min 12 sec = 8:27:12 a.m

Answer 2

Step-by-step explanation:

We know that in order to find the time when the three lights will change simultaneously again after 7 a.m., we need to find the LCM of 48, 72, and 108. Hence, converting 432 seconds into minutes and seconds, we get: 432 seconds = 7 minutes and 12 seconds.