Quiz Discussion

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]

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

A train is scheduled to cover the distance between two stations 46 km apart in one hour. If it travels 25 km at a speed of 40 km/hr, find the speed for the remaining journey to complete it in the scheduled time :

• 1] 36 km/hr
• 2] 46 km/hr
• 3] 56 km/hr
• 4] 66 km/hr

A person can row a boat d km upstream and the same distance downstream in 5 hours 15 minutes. Also, he can row the boat 2d km upstream in 7 hours. How long will it take to row the same distance 2d km downstream?

• 1]

  \(\frac{{3}}{{2}}\) hours

• 2]

  7 hours

• 3]

  \(\frac{{29}}{{4}}\) hours

• 4]

  \(\frac{{7}}{{2}}\) hours

A man completes a certain journey by a car. If he covered 30% of the distance at the speed of 20kmph. 60% of the distance at 40km/h and the remaining of the distance at 10 kmph, his average speed is:

• 1] 25 km/h
• 2] 28 km/h
• 3] 30 km/h
• 4] 33 km/h

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 starts 3 Minutes after B for a place 4.5 km distant. B, on reaching his destination, immediately returns and after walking a km meets A. If A can walk 1 Km in 18 minutes,then what is B's speed?

• 1] 4 km/h
• 2] 6 km/h
• 3] 7 km/h
• 4] 5 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

A train 100 m long is running at the speed of 30 km/hr. The time (in second) in which it passes a man standing near the railway line is :

• 1] 10 seconds
• 2] 11 seconds
• 3] 12 seconds
• 4] 15 seconds

Train A leaves Ludhiana for Delhi at 11 am, running at the speed of 60 km/hr. Train B leaves Ludhiana for Delhi by the same route at 2 pm on the same day, running at the speed of 72 km/hr. At what time will the two trains meet each other ?

• 1] 2 am on the next day
• 2] 5 am on the next day
• 3] 5 pm on the next day
• 4] None of these