Quiz Discussion

One third of a certain journey is covered at the rate of 25 km/hr, one forth at the rate of 30 km/hr and the rest at 50 km/hr. The average speed for the whole journey is :

• 1]

  35 km/hr

• 2]

  \(33\frac{1}{3}\) km/hr

• 3]

  30 km/hr

• 4]

  \(37\frac{1}{12}\) km/hr

A man crosses a road 250 metres wide in 75 seconds. His speed in km/hr is :

• 1] 10 km/hr
• 2] 12 km/hr
• 3] 12.5 km/hr
• 4] 15 km/hr

The speed of a bus is 72 km /hr. The distance covered by the bus in 5 seconds is :

• 1] 100 metres
• 2] 60 metres
• 3] 50 metres
• 4] 74.5 metres

Walking \(\frac{3}{4}\) of his normal speed, Rabi is 16 minutes late in reaching his office. The usual time is taken by him to cover the distance between his home and office:

• 1] 48 min.
• 2] 60 min.
• 3] 42 min.
• 4] 62 min.
• 5] 66 min.

A and B travel the same distance at speed of 9 km/hr and 10 km/hr respectively. If A takes 36 min more than B, the distance travelled by each is :

• 1] 48 km
• 2] 54 km
• 3] 60 km
• 4] 66 km

Two trains start from P and Q respectively and travel towards each other at a speed of 50 km/hr and 40 km/hr respectively. By the time they meet the first train has travelled 100 km more than second. The distance between P and Q is:

• 1]

  500 km

• 2]

  630 km

• 3]

  660 km

• 4]

  900 km

In a flight of 6000 km, an aircraft was slowed down due to bad weather. The average speed for the trip was reduced by 400 kmph and the time of flight increased by 30 minutes. The original planned duration of the flight was :

• 1]

  \({2\frac{1}{2}}\) hours

• 2]

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

• 3]

  \({4\frac{1}{3}}\) hours

• 4]

  \({5\frac{1}{3}}\) hours

A man covered a certain distance at some speed. Had he moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. The distance (in km) is :

• 1]

  35 km

• 2]

  \(36\frac{2}{3}\) km

• 3]

  \(37\frac{1}{2}\) km

• 4]

  40 km

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 performs \(\frac{2}{15}\) of the total journey by rail, \(\frac{9}{20}\) by bus and the remaining 10 km, on the cycle. His total journey is :

• 1] 31.2 km
• 2] 38.4 km
• 3] 32.8 km
• 4] 24 km