Quiz Discussion

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

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 person travels from P to Q at a speed of 40 kmph and returns by increasing his speed by 50%. What is his average speed for both the trips ?

• 1] 36 kmph
• 2] 45 kmph
• 3] 48 kmph
• 4] 50 kmph

A train running at a speed of 54 km/hr crosses a platform in 30 seconds. The platform is renovated and its length is doubled. Now, the same train running at same speed crosses the platform in 46 seconds. Find the length of the train.

• 1] 180 metres
• 2] 200 metres
• 3] 210 metres
• 4] 240 metres
• 5] 450 meters

A motorboat in still water travels at speed of 36 kmph. It goes 56 km upstream in 1 hour 45 minutes. The time taken by it to cover the same distance down the stream will be:

• 1] 2 Hours 25 Minutes
• 2] 3 Hours
• 3] 1 Hours 24 Minutes
• 4] 2 Hours 21 Minutes

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

A train 300 m long passed a man walking along the line in the same direction at the rate of 3 km/hr in 33 sec. The speed of the train is :

• 1]

  30 km/hr

• 2]

  32 km/hr

• 3]

  \(32\frac{8}{{11}}\)  km/hr

• 4]

  \(35\frac{8}{{11}}\)  km/hr

A person can row \(7\frac{1}{2}\) km an hour in still water. Finds that it takes twice the time to row upstream than the time to row downstream. The speed of the stream is:

• 1] 2 kmph
• 2] 2.5 kmph
• 3] 3 kmph
• 4] 4 kmph

One of the two buses completes a journey of 300 km in 7½ hours an the other a journey of 450 km in 9 hours.  The ratio of their average speeds is:

• 1]

  2:3

• 2]

  3:4

• 3]

  4:5

• 4]

  8:9

A train covers a distance of 10 km in 12 minutes. If its speed is decreased by 5 km/hr, the time taken by it to cover the same distance will be :

• 1]

  10 minutes

• 2]

  13 minutes 20 seconds

• 3]

  13 minutes

• 4]

  11 minutes 20 seconds