Q.
A. 30 km/hr
B. 45 km/hr
C. 60 km/hr
D. 75 km/hr
E. None of the above
Correct choice: C
Explanation:
Let the speed of the slower train be x m/sec.
Then, speed of the faster train = 2x m/sec.
Relative speed = (x + 2x) m/sec = 3x m/sec.
24x = 200
= 60 km/hr.