Two train Rajdhani and Satabdi express leaves from Delhi and Lucknow respectively. They meet each other at a point from where Rajadhani express reaches to Lucknow in 6.25 hours and Satabdi express reaches to Delhi in 9 hours. Find the time taken by the slower train to cover this distance.?

Option 3 : 16.5 hours

Given:

Rajdhani express reaches Lucknow in 6.25 hours after meeting and Satabdi express reaches Delhi in 9 hours after meeting.

Formula used:

S₁/S₂ = √(t₂/t₁)

Where S₁ = Speed of first train

S₂ = Speed of second train

And t₂ = time taken by second train after meeting, t₁ = time taken by second train after meeting

Calculation:

S₁/S₂ = √(9/6.25) = 3/2.5 = 6/5

So the speed of slower train i.e. Satabdi express = 5x

And speed of faster train Rajdhani express = 6x

Total distance = 6x × 6.25 + 9 × 5x = 37.5x + 45x = 82.5x

∴ Time taken by slower train = 82.5x/(5x) = 16.5 hours