Speed of train A = 75 km/hr and speed of train B = 50 km/hr Let distance travelled by train B = d km ⇒ Distance travelled by train A = ( d + 175 ) km Time taken by both the trains is equal as they start at the same time. Using, time = distance/speed ⇒
d+175
75
=
d
50
⇒
d+175
3
=
d
2
⇒ 2d+350=3d ⇒ 3d−2d=d=350 ∴ between A and B = d+(d+175)=2d+175 = 2(350)+175=700+175=875 km