Quiz Discussion

A, B and C start together from the same place to walk round a circular path of length 12km. A walks at the rate of 4 km/h, B 3 km/h and C \(\frac{3}{2}\) km/h. They will meet together at the starting place at the end of:

• 1] 10 hours
• 2] 12 hours
• 3] 15 hours
• 4] 24 hours

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

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

From two places, 60 km apart, A and B start towards each other at the same time and meet each other after 6 hours. If A traveled with \(\frac{2}{3}\) of his speed and B traveled with double of his speed, they would have met after 5 hours. The speed of A is:

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

A man walks a certain distance in certain time, if he had gone 3 km per hour faster, he would have taken 1 hour less than the scheduled time. If he had gone 2 km per hour slower, he would have taken one hour longer on the road. The distance (in km) is :

• 1] 60
• 2] 45
• 3] 65
• 4] 80

A jeep is chasing a car which is 5 km ahead. Their respective speeds are 90 km/hr and 75 km/hr. After how many minutes will the jeep catch the car ?

• 1] 10 min
• 2] 20 min
• 3] 24 min
• 4] 25 min

A car goes 10 meters in a second. Find its speed in km/hour.

• 1] 40 km/hr
• 2] 32 km/hr
• 3] 48 km/hr
• 4] 36 km/hr

Two trains 105 meters and 90 meters long, run at the speeds of 45 kmph and 72 kmph respectively, in opposite directions on parallel tracks. The time which they take to cross each other, is:

• 1] 8 seconds
• 2] 6 seconds
• 3] 7 seconds
• 4] 5 seconds

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

If A travels to his school from his house at the speed of 3 km/h, then he reaches the school 5 minutes late. If he travels at the speed of 4 km/h, he reaches the school 5 minutes earlier than school time. The distance of his school from his house is:

• 1] 1 km
• 2] 2 km
• 3] 3 km
• 4] 4 km