IBPS RRB Office Assistant 2020 Paper

Let the initial speed of train be × km/h. Distance between stations A and B = d km
Case I With initial speed,
Time taken =

Distance

Speed

⇒ 2=

d

x

...(i)
Case II With decreased speed,
Time taken =

Distance

Speed

⇒ 3=

d

(x−6)

...(ii)
From Eqs. (i) and (ii), we get
2x = 3(x - 6)
⇒ 2x = 3x - 18
⇒ 3x - 2x = 18
⇒ x = 18 km/h
On putting the value of x in Eq. (i), we get
2=

d

18

⇒ d=2 × 18 = 36km
∴ Initial speed of train = 18 km/h and distance between two stations= 36 km