Quiz Discussion

A bus covers three successive 3 km stretches at speed of 10 km/hr, 20 km/hr and 60 km/hr respectively. Its average speed over this distance is :

• 1] 30 km/hr
• 2] 25 km/hr
• 3] 18 km/hr
• 4] 10 km/hr

If a person walks at 14 km/hr instead of 10 km/hr, he would have walked 20 km more. The actual distance travelled by him is:

• 1] 50 km
• 2] 56 km
• 3] 70 km
• 4] 80 km

Without stoppage, a train travels a certain distance with an average speed of 60 km/h, and with stoppage it covers the same distance with an average speed of 40 km/h. On an average, how many minutes per hour does train stop during the journey ?

• 1] 20 min/hour
• 2] 15 min/hour
• 3] 10 min/hour
• 4] 12 min/hour

An athlete claimed that his timing for a 100 m dash should be corrected because the starting signal was gives by a gun fired from a point 10 m away from him and the timekeeper was standing close to the gun. The error due to this could be (in seconds) :

• 1] 0.03 sec
• 2] 0.1 sec
• 3] 0.5 sec
• 4] 0.7 sec

A man walk a certain distance and rides back in 4 hours 30 minutes. He could ride both ways in 3 hours. The time required by the man to walk both ways is :

• 1] 4 hours 30 minutes
• 2] 4 hours 45 minutes
• 3] 5 hours
• 4] 6 hours

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

Points 'A' and 'B' are 70 km apart on a highway and two cars start at the same time. If they travel in the same direction, they meet in 7 hours, but if they travel towards each other they meet in one hour. Find the speed of the two cars (in km/hr).

• 1] 20, 30
• 2] 40, 30
• 3] 30, 50
• 4] 20, 40

A racetrack is in the form of a right triangle. The longer of the legs of track is 2 km more than the shorter of the legs (both these legs being on a highway). The start and end points are also connected to each other through a side road. The escort vehicle for the race took the side road and rode with a speed of 30 km/h and then covered the two intervals along the highway during the same time with a speed of 42 km/h. find the length of the race track.

• 1] 14 km
• 2] 10 km
• 3] 24 km
• 4] 36 km
• 5] 30 km

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

Two runner start running together for a certain distance, one at 5 km/h and another at 8 km/h. The former arrives one and half an hour before the latter. The distance in Km is :

• 1] 12 km
• 2] 20 km
• 3] 25 km
• 4] 36 km