Question

Two trains $T_{1}$ and $T_{2}$ start at the same time from stations P and Q to reach stations Q and P. After passing each other, they take 12 hours and 3 hours to reach their destinations. If the fastest train is 48kmph, what is the speed of the other train?

• A. 96kmph
• B. 24kmph
• C. 36kmph
• D. 25kmph

Hint:

$\frac{Speed_1}{Speed_2} = \sqrt{\frac{Time_2}{Time_1}}$ for trains meeting and proceeding.

Answer 1

The Correct Option is B

Step 1: Concept
Ratio of speeds of two trains after passing each other is $S_1 / S_2 = \sqrt{t_2 / t_1}$.

Step 2: Analysis
$t_1 = 12h$, $t_2 = 3h$.
Ratio $S_1 / S_2 = \sqrt{3 / 12} = \sqrt{1 / 4} = 1/2$.

Step 3: Calculation
$S_2$ (fastest) = $48kmph$.
$S_1 / 48 = 1/2 \implies S_1 = 24kmph$.

Step 4: Conclusion
The slower train speed is 24kmph. Final Answer: (B)