Quiz Discussion

A boy is running at a speed of p kmph to cover a distance of 1 km. But, due to the slippery ground, his speed is reduced by q kmph (p > q). If he takes r hours to cover the distance, then:

• 1]

  \(\frac{1}{r} = p - q\)

• 2]

  r = p - q

• 3]

  \(\frac{1}{r} = p + q\)

• 4]

  r = p + r

A train approaches a tunnel AB. Inside the tunnel is a cat located at a point that is \(\frac{3}{8}\) of the distance AB measured from entrance A. When the train whistles, that cat runs. If the cat moves to entrance A of the tunnel, the train catches the cat exactly at the entrance. If the cat moves to exit B, the train catches the cat at exactly the exit. The ratio of the speed of the train to that of the cat is of the order :

• 1] 3 :1
• 2] 4 : 1
• 3] 5 : 1
• 4] None of these

A train passes two persons walking in the same direction at a speed of 3 kmph and 5 kmph respectively in 10 seconds and 11 seconds respectively. The speed of the train is

• 1] 28 kmph
• 2] 27 kmph
• 3] 25 kmph
• 4] 24 kmph

A train travelling with a speed of 60 kmph catches another train travelling in the same direction and then leaves it 120 m behind in 18 seconds. The speed of the second train is

• 1] 26 kmph
• 2] 35 kmph
• 3] 36 kmph
• 4] 63 kmph

A square playground measure 1127.6164 sq.m. If a man walks \(2\frac{9}{{20}}\) m a minute, the time taken by him to walk one round around it is approximately :

• 1] 50.82 minutes
• 2] 54.82 minutes
• 3] 54.62 minutes
• 4] 50.62 minutes

A car after traveling 18 km from a point A developed some problem in the engine and the speed became \(\frac{4}{5}\) th of its original speed. As a result, the car reached point B 45 minutes late. If the engine had developed the same problem after traveling 30 km from A, then it would have reached 36 minutes late. The original speed of the car (in km/h) is:

• 1] 25 kmph
• 2] 30 kmph
• 3] 20 kmph
• 4] 35 kmph
• 5] None of these

A certain distance is covered at a certain speed. If half of this distance is covered in double the time, the ratio of the two speed is :

• 1] 1 : 16
• 2] 4 : 1
• 3] 2 : 1
• 4] 1 : 4

The wheel of an engine of 300 cm in circumference makes 10 revolutions in 6 seconds. What is the speed of the wheel (in km/h)?

• 1] 18
• 2] 20
• 3] 27
• 4] 36

An athlete claimed that his timing for a 100 m dash should be corrected because the starting signal was gives by a gun fired from a point 10 m away from him and the timekeeper was standing close to the gun. The error due to this could be (in seconds) :

• 1] 0.03 sec
• 2] 0.1 sec
• 3] 0.5 sec
• 4] 0.7 sec

A gun is fired at a distance of 1.7 km from Ram and he hears the sound after 25 seconds. The speed of sound in meter per second is

• 1] 60 m/s
• 2] 62 m/s
• 3] 64 m/s
• 4] 68 m/s