Quiz Discussion

A coolie standing on a railway platform observe that a train going in one direction takes 4 second to pass him. Another train of same length going in opposite direction takes 5 seconds to pass him. The time taken (in seconds) by two train to cross each other will be:

• 1]

  35 seconds

• 2]

  36.5 seconds

• 3]

  \(\frac{{40}}{9}\) seconds

• 4]

  36 seconds

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 train, 300m long, passed a man, walking along the line in the same direction at the rate of 3 kmph in 33 seconds. The speed of the train is:

• 1]

  30 kmph

• 2]

  32 kmph

• 3]

  \(32\frac{8}{{11}}\) kmph

• 4]

  \(35\frac{8}{{11}}\) kmph

A star is 8.1 × 1013 km away from the earth. Suppose light travels at the speed of 3.0 × 105 km per second. How long will it take the light from the star to reach the earth ?

• 1] 7.5 × 103 hours
• 2] 7.5 × 104 hours
• 3] 2.7 × 1010 seconds
• 4] 2.7 × 1011 seconds

Sabarmati express takes 18 seconds to pass completely through a station 162 m long and 15 seconds through another station 120 m long. The length of the train is :

• 1] 132 m
• 2] 100 m
• 3] 80 m
• 4] 90 m

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

A man travels 600 km by train at 80 km/hr, 800 km by ship at 40 km/hr, 500 km by aeroplane at 400 km/hr and 100 km by car at 50 km/hr. What is the average speed for the entire distance :

• 1]

  \({ \text{60 km/hr}}\)

• 2]

  \(60\frac{5}{123}{ \text{ km/hr}}\)

• 3]

  \({ \text{62 km/hr}}\)

• 4]

  \(65\frac{5}{123}{ \text{ km/hr}}\)

A plane left half an hour later than the scheduled time and in order to reach its destination 1500 kilometers away in time, it had to increase its speed by 33.33 percent over its usual speed. Find its increased speed.

• 1] 250 kmph
• 2] 500 kmph
• 3] 750 kmph
• 4] 1000 kmph
• 5] 1200 kmph

A thief seeing a policeman at a distance of 150 metres starts running at 10 kmph and the policeman gives immediate chase at 12 kmph. When the thief is overtaken the thief has traveled a distance of:

• 1] 750 m
• 2] 900 m
• 3] 800 m
• 4] 1 km

A bus moving at a speed of 45 km/hr catches a truck 150 metres ahead going in the same direction in 30 seconds. The speed of the truck is :

• 1] 27 km/hr
• 2] 24 km/hr
• 3] 25 km/hr
• 4] 28 km/hr