Question

a railway passenger counts the telegraph posts on the line as he passes them. if they are 50 m apart from each other and the train is running at the rate of 40 km/hr. how many posts will he pass per minute ?

Answer 1

Solution
speed = 40 km / hr
         = 40 X ( 5/18 )  m/s
       
now distance travelled by the train in 1 minute  (ie  60 seconds )

distance =  speed X time
             = ( 40 X ( 5/18 ) ) X 60
             = 666.667 m

now the distance between the posts = 50 m

so number = ( 666.667 / 50 )
                 =13.33
                 = 13

But by the basic concepts of counts between poles  or posts

number = answer + 1

           = 14 posts

The railway passenger would pass 14 posts