Quiz Discussion

A man goes downstream with a boat to some destination and returns upstream to his original place in 5 hours. If the speed of the boat in still water and the stream are 10 kmph and 4 kmph respectively, the distance of the destination from the starting place is:

• 1] 16 km
• 2] 18 km
• 3] 21 km
• 4] 25 km

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

If a 250 m long train crosses a platform of same length as that of the train in 25 seconds, then the speed of the train is:

• 1] 150 m/sec
• 2] 200 m/sec
• 3] 20 km/h
• 4] 72 km/h

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

A motorboat in still water travels at speed of 36 kmph. It goes 56 km upstream in 1 hour 45 minutes. The time taken by it to cover the same distance down the stream will be:

• 1] 2 Hours 25 Minutes
• 2] 3 Hours
• 3] 1 Hours 24 Minutes
• 4] 2 Hours 21 Minutes

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

Two ports A and B are 300 km apart. Two ships leave A for B such that the second leaves 8 hours after the first. The ships arrive at B simultaneously. Find the time the slower ship spent on the trip if the speed of one of them is 10 km/h higher than that of the other.

• 1] 25 hours
• 2] 20 hours
• 3] 15 hours
• 4] 20 hours
• 5] 24 hours

Car A travels at the speed of 65 km/hr and reaches its destination in 8 hours. Car B travels at the speed of 70 km/hr and reaches its destination in 4 hours. What is the ratio of the distance covered by car A and car B respectively ?

• 1] 7 : 11
• 2] 13 : 7
• 3] 7 : 13
• 4] 11 : 7
• 5] None of these

Two trains for Mumbai leave Delhi at 6 am and 6.45 am and travel at 100 kmph and 136 kmph respectively. How many kilometers from Delhi will the two trains be together:

• 1] 262.4 km
• 2] 260 km
• 3] 283.33 km
• 4] 275 km
• 5] None of these

A is travelling at 72 km per hour on a highway while B is travelling at a speed of 25 mitres per second. What us the difference in their speeds in mitres per second ?

• 1]

  \(1\frac{1}{2} \)m/sec

• 2]

  2 m/sec

• 3]

  3 m/sec

• 4]

  5 m/sec