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 ship leaves on a long voyage. When it is 18 miles from shore, a sea plane, whose speed is ten times that of the ship, is sent to deliver mail. How far from the shore does the sea plane catch up with the ship?

• 1] 24 miles
• 2] 25 miles
• 3] 22 miles
• 4] 20 miles
• 5] None of these

The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 km in 4 hours, then the speed of the first train is:

• 1] 70 km/hr
• 2] 75 km/hr
• 3] 84 km/hr
• 4] 87.5 km/hr

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

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

A train approaches a tunnel AB. Inside the tunnel, a cat is located at a point i.e. \(\frac{5}{{12}}\) of the distance AB measured from entrance A. When the train whistles the Cat runs. If the cat moves to exit B, the train catches the cat exactly at the exit. The speed of the train is greater than the speed of the cat by what order?

• 1] 1 : 6
• 2] 3 : 5
• 3] 6 : 1
• 4] 5 : 4
• 5] None of these

A man covered a certain distance at some speed. Had he moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. The distance (in km) is :

• 1]

  35 km

• 2]

  \(36\frac{2}{3}\) km

• 3]

  \(37\frac{1}{2}\) km

• 4]

  40 km

Amit travelled black to home in a car, after visiting his friend in a distant village. When he stated at his friend's house the car had exactly 18 litres of petrol in it. He travelled along at a steady 40 kilometres per hour and managed a 10 kilometres per litre of petrol. As the car was old, the fuel tank lost fuel at the rate of half a litre per hour. Amit was lucky as his car stopped just in front of his home because it had rum out of fuel and he only just made it. How far was it from his friend's home to Amit's home ?

• 1] 150 km
• 2] 170 km
• 3] 180 km
• 4] None of these

Two men P and Q start a journey from the same place at a speed of 3 km/hr and \(3\frac{1}{2}\) km/hr respectively. If they move in the same direction then what is the distance of them after 4 hours?

• 1]

  3 km

• 2]

  \(2\frac{1}{2} \)km

• 3]

  2 km

• 4]

  \(\frac{1}{2}\) km

Two rifles are fired from the same place at a difference of 11 minutes 45 seconds. But a man who is coming towards the place in a train hears the second sound after 11 minutes. Find the speed of train. (speed of sound = 330 m/s)

• 1] 72 kmph
• 2] 36 kmph
• 3] 81 kmph
• 4] 108 kmph
• 5] None of these