All light was seen at interval if 30 seconds It was seen of the fisrt line at 1hr.54 min 50 seconds a.m and the last time at 3 hrs 17 min 49 seconds a.m. How many times was the light seen ?

Explanation

First Time `=1 hour 54 mins 50 seconds`


Last Time `=3 hours 17 mins 49 seconds`


Duration `=(3h 17min 49s)-(1 h 54 min 50 s)`


`=1 h 22 mins 59 s`


`=4979 seconds`


Number of `13 seconds` interval `=4979 div 13`


`=383`


Total number of times the light is seen `=383+1`


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