Quiz Discussion

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 person travels three equal distance at a speed of x km/hr, y km/hr and z km/hr respectively. What is the average speed for the whole journey ?

• 1]

  \(\frac{{xyz}}{{3\left( {xy + yz + zx} \right)}}\)    km/hr

• 2]

  \(\frac{{xyz}}{{\left( {xy + yz + zx} \right)}}\)    km/hr

• 3]

  \(\frac{{\left( {xy + yz + zx} \right)}}{{xyz}}\)    km/hr

• 4]

  \(\frac{{3xyz}}{{\left( {xy + yz + zx} \right)}}\)    km/hr

In a race of one kilometre. A gives B a start of 100 metres and still wins by 20 seconds. But if A gives B a start of 25 seconds, B wins by 50 metres. The time taken by A to run kilometre is :

• 1]

  17 sec

• 2]

  \(\frac{{500}}{{29}}{ \text{sec}}\)

• 3]

  \(\frac{{1200}}{{29}}{ \text{sec}}\)

• 4]

  \(\frac{{700}}{{29}}{ \text{sec}}\)

Ravi and Ajay start simultaneously from a place A towards B 60 km apart. Ravi's speed is 4km/h less than that of Ajay. Ajay, after reaching B, turns back and meets Ravi at a places 12 km away from B. Ravi's speed is:

• 1] 12 km/h
• 2] 10 km/h
• 3] 8 km/h
• 4] 6 km/h

The distance from bhopal to indore is 200 km. A bus start from indore to bhopal every half an hour. If the speed of each bus is 40 km/hr. How many bus will a bhopal to indore bus cross by the time it reach indore?

• 1]

  21

• 2]

  22

• 3]

  23

• 4]

  24

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

Ashok left from place A for place B at 8 am and Rahul left place B for place A at 10.00 am the distance between place A and B is 637 km. If Ashok and Rahul are travelling at a uniform speed of 39 kmph and 47 kmph respectively, at what time will they meet ?

• 1] 5.30 pm
• 2] 4.30 pm
• 3] 5 pm
• 4] 4 pm

Two trains start simultaneously from two stations Howrah and Delhi, respectively towards each other on the same track. The distance between the two stations is 560 km and the speeds of trains are 30 kmph and 40 kmph.

• 1] 70 km
• 2] 560 km
• 3] 640 km
• 4] 650 km
• 5] None of these

A walk at a uniform rate of 4 km an hour; and 4 hr after his start, B bicycles after him at the uniform rate of 10 km an hour. How far from the starting point will B catch A ?

• 1] 16.7 km
• 2] 18.6 km
• 3] 21.5 km
• 4] 26.7 km

A boat covers 48 km upstream and 72 km downstream in 12 hours, while it covers 72 km upstream and 48 km downstream in 13 hours The speed of stream is :

• 1] 2 kmph
• 2] 2.2 kmph
• 3] 2.5 kmph
• 4] 4 kmph