Question

A train met with an accident 120 km from station A. It completed the remaining journey at 5/6 of its previous speed and reached 2 hours late at station B.Had the accident taken place 300 km further, it would have been only 1 hour late. What is the speed of the train?

• A. 100 km/h
• B. 120 km/h
• C. 60 km/h
• D. 50 km/h

Answer 1

The correct option is C 60 km/h


$P_1$ $\to$ Place of accident
$P_2$ $\to$ Imaginary place of accident
For the distance x
Speed Time
$\frac{1}{6}\downarrow$ $\frac{1}{5}\uparrow$ = 1h
Thus, the usual time required for the distance x km is 5*1 = 5 hours.
For the distance (x + 300)
Speed Time
$\frac{1}{6}\downarrow$ $\frac{1}{5}\uparrow$ = 2h
Thus, the usual time required for the distance (x + 300) km/h
5 $\times$ 2 = 10 h.
It means he covers 300 km distance in 5 hours
$\therefore$ Speed $=\frac{300}{5}=60km/h$ (normal speed)