Question

Two trains started from Kalka railway station on two parallel tracks in the same direction. The speed of the trains is 45 m/sec and 25 m/sec respectively. Find the distance between the trains after 75 minutes.

1. 70 km
2. 80 km
3. 90 km
4. 100 km
5. 110 km

Answer 1

Correct Answer - Option 3 : 90 km

Given:

Speed of trains are 45 m/sec & 25 m/sec

Concept used:

Time taken = d/(s₁ – s₂)

(Moving in same direction)

d = distance covered

s₁ = Speed of train 1

s₂ = Speed of train 2

Calculation:

{d/(45 – 25)} = 75 

⇒ d/20 = 75 × 60  

⇒ d = 20 × 4500 = 90000 m = 90 km

∴ The distance between the trains after 75 minutes is 90 km.