Quiz Discussion

A man goes to a place on bicycle at speed of 16 km/hr and comes back at lower speed. If the average speed is 6.4 km/hr in total, then the return speed (in km/hr) is :

• 1] 10 km/hr
• 2] 8 km/hr
• 3] 6 km/hr
• 4] 4 km/hr

A thief sees a jeep at a distance of 250 m, coming towards him at 36 km/h. Thief takes 5 seconds to realize that there is nothing but the police is approaching him by the jeep and start running away from police at 54 km/h. But police realise after 10 second, when the thief starts running away, that he is actually a thief and gives chase at 72 km/h. How long after thief saw police did catchup with him and what is the distance police had travel to do so?

• 1] 50 s, 1000 m
• 2] 65 s, 1150 m
• 3] 65 s, 1300 m
• 4] 45 s, 1050 m
• 5] None of these

A train passes two bridges of length 800 m and 400 m in 100 seconds and 60 seconds respectively. The length of the train is:

• 1] 80m
• 2] 90m
• 3] 200m
• 4] 150m

A girl while walking diametrically across a semicircular playground, takes 3 minutes less than if she had kept walking round the circular path from A to B. If she walks 60 metres a minute, what is diameter of the play ground?

• 1] 60 m
• 2] 48 m
• 3] 84 m
• 4] 315 m
• 5] None of these

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

A car traveling with \(\frac{5}{7}\) of its usual speed covers 42 km in 1 hr 40 min 48 sec. What is the usual speed of the car?

• 1]

  \(17\frac{6}{7}\) km/hr

• 2]

  35 km/hr

• 3]

  25 km/hr

• 4]

  30 km/hr

If A travels to his school from his house at the speed of 3 km/h, then he reaches the school 5 minutes late. If he travels at the speed of 4 km/h, he reaches the school 5 minutes earlier than school time. The distance of his school from his house is:

• 1] 1 km
• 2] 2 km
• 3] 3 km
• 4] 4 km

A soldier fired two bullets at an interval of 335 seconds moving at a uniform speed V1. A terrorist who was running ahead of the soldier in same direction, hears the two shots at an interval of 330 seconds. If the speed of sound is 1188 km/h, then who is the faster and how much?

• 1] Soldier, 22 km/h
• 2] Terrorist, 25 km/h
• 3] Soldier, 18 km/h
• 4] Terrorist, 20 km/h
• 5] None of these

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 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