Quiz Discussion

Two boats A and B start towards each other from two places, 108 km apart. Speed of the boats A and B in still water are 12 km/h and 15 km/h respectively. If A proceeds down and B up the stream, they will meet after:

• 1] 4.5 hours
• 2] 4 hours
• 3] 5.4 hours
• 4] 6 hours

A train is 250 m long. If the train takes 50 second to cross a tree by the railway line, then the speed of the train on Km /hr is :

• 1] 9 km/hr
• 2] 5 km/hr
• 3] 18 km/hr
• 4] 10 km/hr

A plan left 40 minutes late due to bad whether and order to reach its destination 1600 km away in time, it had increase its speed by 400 kmph from its usual speed. Find the usual speed of the plane?

• 1] 600 km/hour
• 2] 400 km/hour
• 3] 1000 km/hour
• 4] 800 km/hour

It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the cars is:

• 1] 2 : 3
• 2] 3 : 2
• 3] 3 : 4
• 4] 4 : 3

A thief is noticed by a policeman from a distance of 200 m. The thief starts running and the policeman chases him. The thief and the policeman run at the rate of 10 km and 11 km per hour respectively. What is the distance between them after 6 minutes ?

• 1]

  100 m

• 2]

  150 m

• 3]

  190 m

• 4]

  290 m

A 75 metres long train is moving at 20 kmph. It will cross a man standing on the platform in :

• 1] 12 seconds
• 2] 14 seconds
• 3] 13.5 seconds
• 4] 15.5 seconds

A train met with an accident 120 km from station A. It completed the remaining journey at \(\frac{5}{6}\) 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?

• 1] 100 km/h
• 2] 12 km/h
• 3] 60 km/h
• 4] 50 km/h

Car A travels at the speed of 65 km/hr and reaches its destination in 8 hours. Car B travels at the speed of 70 km/hr and reaches its destination in 4 hours. What is the ratio of the distance covered by car A and car B respectively ?

• 1] 7 : 11
• 2] 13 : 7
• 3] 7 : 13
• 4] 11 : 7
• 5] None of these

A is twice fast as B and B is thrice fast as C is. The journey covered by C in \(\frac{3}{2}\) hours will be covered by A is:

• 1] 15 minutes
• 2] 20 minutes
• 3] 30 minutes
• 4] 1 hour

Two planes move along a circle of circumference 1.2 km with constant speeds. When they move in different directions, they meet every 15 seconds and when they move in the same direction, one plane overtakes the other every 60 seconds. Find the speed of the slower plane.

• 1] 0.04 km/s
• 2] 0.03 km/s
• 3] 0.05 km/s
• 4] 0.02 km/s
• 5] None of these