Question

pls help me with proper explanation​

Answer 1

Let the speed of the train be S. And length of the train be x.

When a train crosses a man, it travels its own distance.

According to question;

x/[(s−3)×(5/18)]=10

or,18x=50×s−150....(i)

and

x/[(x−5)×(5/18)]=11

18x=55×s−275......(ii)

(Equating equation (i) and (ii)

50×s−150=55×s−275

or,5×s=125or,s=25kmph