Question

A train 110 m long travels at 30 km per hour. How long will it take to cross a platform 90 m long

Answer 1

Speed in m/sec - 25/3m/sec
Total distance to be covered - 110+90=200m
Let the train cover 200m in x sec.
This is a case of direct variation.
25/3=200/x
=> 25x=200×3
=> x= 600/25
=> x=24
Therefore, the train will take 24 secs. to cross the platform.

Answer 2

speed = 30 km per hr
=30000/3600=25/3m per sec
total distance to be covered=110m+90m
=200m
25/3m=1sec
1m = 1/(25/3)sec
200m= 3/25*200
= 24sec 
hope this will help u and tap thankd and mark brainliest ans plzzzzz..