Quiz Discussion

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

I started on my bicycle at 7 am to reach a certain place. After going a certain distance, my bicycle went out of order. Consequently, I rested for 35 minutes and came back to my house walking all the way. I reached my house at 1 pm. If my cycling speed is 10 kmph and my walking speed is 1 kmph, then on my bicycle I covered a distance of :

• 1]

  \(4\frac{61}{66}\) km

• 2]

  \(13\frac{4}{9}\) km

• 3]

  \(14\frac{3}{8}\) km

• 4]

  \(15\frac{10}{21}\) km

Two trains 150 m and 120 m long respectively moving from opposite direction cross each other in 10 sec. If the speed of the second train is 43.2 km/hr, then the speed of the first train is :

• 1] 54 km/hr
• 2] 50 km/hr
• 3] 52 km/hr
• 4] 51 km/hr

Two men start together to walk a certain distance, one at 4 km/hr and another at 3 km/hr. The former arrives half an hour before the latter. Find the distance :

• 1] 8 km
• 2] 7 km
• 3] 6 km
• 4] 9 km

The speed of 90 km per hour is same as :

• 1] 9 m/s
• 2] 20 m/s
• 3] 25 m/s
• 4] 28 m/s

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

Two cyclists start on a circular track from a given point but in opposite directions with speeds of 7 m/sec and 8 m/sec respectively. If the circumference of the circle is 300 metres, after what time will they meet at the starting point ?

• 1] 20 sec
• 2] 100 sec
• 3] 200 sec
• 4] 300 sec

A train, 300m long, passed a man, walking along the line in the same direction at the rate of 3 kmph in 33 seconds. The speed of the train is:

• 1]

  30 kmph

• 2]

  32 kmph

• 3]

  \(32\frac{8}{{11}}\) kmph

• 4]

  \(35\frac{8}{{11}}\) kmph

A car goes 20 metres in a second. Find its speed in km/hr.

• 1] 20 km/hr
• 2] 18 km/hr
• 3] 72 km/hr
• 4] 36 km/hr

Two boats, travelling at 5 km/h and 10 km/h, head directly towards each other. They begin at a distance of 20 km from each other. How far apart are they (in km) one minute before they collide?

• 1]

  \(\frac{{1}}{{12}}\)

• 2]

  \(\frac{{1}}{{6}}\)

• 3]

  \(\frac{{1}}{{4}}\)

• 4]

  \(\frac{{1}}{{3}}\)

• 5]

  None of these