Question

An express train makes a run of 240 km/hr at a certain speed. Another train whose speed is 12km/hr less takes one hour longer to cover the same distance. Find the speed of the train in km/hr

Answer 1

an express train =240km/hr
another train =12km/hr less takes
=240-12
one hour longer to cover the same distance =228 ÷2
=114km/hr ans

Answer 2

Let T hr be the total time taken by first train to cover total distance 240 km at a speed of xkm/hr
T=240/x
Let T' hr be the time taken by another train
So,T'= T+1=(240/x)+1....a
Now,T'=240/(x-12)=....b
Equating eq a & b
240/x-12=240/x+1
[240/(x-12)]-240-x=1
x=-48 or 60
As speed cannot be negative
Speed of train =60km/hr