21. How many seconds will a 500 meter long train take to cross a man walking with a speed of 3 km/hr in the direction of the moving train if the speed of the train is 63 km/hr?
A. 25
B. 30
C. 40
D. 45
22. Two goods train each 500 m long, are running in opposite directions on parallel tracks. Their speeds are 45 km/hr and 30 km/hr respectively. Find the time taken by the slower train to pass the driver of the faster one.
A. 12 sec
B. 24 sec
C. 48 sec
D. 60 sec
23. Two trains are running in opposite directions at the same speed. If the length of each train is 120 meters and they cross each other in 12 seconds, then the speed of each train (in km/hr) is:
A. 10
B. 18
C. 36
D. 72
24. Two trains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post. If the length of each train be 120 meters, in what time (in seconds) will they cross each other traveling in the opposite direction?
A. 10
B. 12
C. 15
D. 20
25. A train 108 m long moving at a speed of 50 km/hr crosses a train 112 m long coming from the opposite direction in 6 seconds. The speed of the second train is:
A. 48 km/hr
B. 54 km/hr
C. 66 km/hr
D. 82 km/hr