Question

The traffic lights at three different goal crossing
change after every his senconds, 72 seconds and tos
Second respectively. If they change Simultaneously
at 7 am, at what time will they change simultanevez
again?​

Answer 1

Answer:

Step-by-step explanation:

Consider the problem

The traffic light at three different road crossing change after every 48seconds,72seconds and 108seconds respectively

So,

48=2×2×2×2×3

72=2×2×2×3×3

108=2×2×3×3×3

​  

 

Therefore, L.CM of 48,72,108 is  

(2×2×2×2×3×3×3)

=432

​  

 

So, time when they change again =432seconds

But we need to find time after 7am So, first we convert 432seconds into minutes.  

Time=432second

=  

60

432

​  

minutes

∴Time=7 minutes12 seconds

​  

 

 

Thus,

Required time =7am+7minutes 12seconds

=7:07:12am

Hope it helps :)