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

• 1] 100 m
• 2] 190 m
• 3] 200 m
• 4] 150 m

A moving train passes a platform 50 m long in 14 seconds and a lamp post in 10 seconds. The speed of the train (in km/hr) is :

• 1] 24 km/hr
• 2] 36 km/hr
• 3] 40 km/hr
• 4] 45 km/hr

Two trains start from P and Q respectively and travel towards each other at a speed of 50 km/hr and 40 km/hr respectively. By the time they meet the first train has travelled 100 km more than second. The distance between P and Q is:

• 1]

  500 km

• 2]

  630 km

• 3]

  660 km

• 4]

  900 km

A person wishes to reach his destination 90 km away 3 hours but for the first half of the journey his speed was 20 km/hr. His average speed for the rest of the journey should be :

• 1] 4 km/hr
• 2] 0.75 km/min
• 3] 1 km/min
• 4] None of these

The speed of a bus is 72 km /hr. The distance covered by the bus in 5 seconds is :

• 1] 100 metres
• 2] 60 metres
• 3] 50 metres
• 4] 74.5 metres

A train 300 m long passed a man walking along the line in the same direction at the rate of 3 km/hr in 33 sec. The speed of the train is :

• 1]

  30 km/hr

• 2]

  32 km/hr

• 3]

  \(32\frac{8}{{11}}\)  km/hr

• 4]

  \(35\frac{8}{{11}}\)  km/hr

A train leaves Delhi at 4.1 pm and reaches Aligargh at 7.25 pm. The average speed of the train is 40 km/hr. What is the distance from Delhi to Aligarh ?

• 1] 120 km
• 2] 130 km
• 3] 135 km
• 4] 140 km

A candle of 6 cm long burns at the rate of 5 cm in 5 hour and an another candle 8 cm long burns at the rate of 6 cm in 4h. What is the time required to each candle to remain of equal lengths after burning for some hours, when they starts to burn simultaneously with uniform rate of burning?

• 1] 1 hours
• 2] 1.5 hours
• 3] 2 hours
• 4] 3 hours
• 5] 4 hours

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