Quiz Discussion

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 train covers a distance of \(193\frac{1}{3}\) km in \(4\frac{1}{4}\) hours with one stoppage of 10 minutes, two of 5 minutes, and one of 3 minutes on the way. The average speed of the train is :

• 1] 48 km/hr
• 2] 50 km/hr
• 3] 55 km/hr
• 4] 60 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

The diameter of each wheel of car is 70 cm. If each wheel rotates 400 times per minutes, then the speed of the car (in km/hr) if : \(\left( {{ \text{Take }}pi = \frac{{22}}{7}} \right)\)

• 1] 5.28 km/hr
• 2] 528 km/hr
• 3] 52.8 km/hr
• 4] 0.528 km/hr

A car goes 20 metres in a second. Find its speed in km/hr.

• 1] 20 km/hr
• 2] 18 km/hr
• 3] 72 km/hr
• 4] 36 km/hr

A train started from station A and proceeded towards station B at a speed of 48 km/hr. Forty-five minutes later another train started from station B and proceeded towards station a at 50 km/hr. If the distance between the two stations is 232 km, at what distance from station A will the trains meet ?

• 1] 108 km
• 2] 132 km
• 3] 144 km
• 4] None of these

Roorkee express normally reaches its destination at 50 km/h in 30 hours. Find the speed at which it travels to reduce the time by 10 hours?

• 1] 38 km/h
• 2] 76 km/h
• 3] 75 km/h
• 4] 60 km/h

The average speed of a train is 20% less on the return journey than on onward journey. The train halts for half an hour at the destination station before starting on the return journey. If the total time taken for the to and fro journey is 23 hours, covering a distance of 1000 km, the speed of the train on the return journey is:

• 1] 60 km/hr
• 2] 50 km/hr
• 3] 40 km/hr
• 4] 55 km/hr

Rani goes to school from her house in 30 minutes. Raja takes 45 minutes in covering the same distance. Find the ratio between time taken by Rani and Raja ?

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