Quiz Discussion

Two boats A and B start towards each other from two places, 108 km apart. Speed of the boats A and B in still water are 12 km/h and 15 km/h respectively. If A proceeds down and B up the stream, they will meet after:

• 1] 4.5 hours
• 2] 4 hours
• 3] 5.4 hours
• 4] 6 hours

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 thief sees a jeep at a distance of 250 m, coming towards him at 36 km/h. Thief takes 5 seconds to realize that there is nothing but the police is approaching him by the jeep and start running away from police at 54 km/h. But police realise after 10 second, when the thief starts running away, that he is actually a thief and gives chase at 72 km/h. How long after thief saw police did catchup with him and what is the distance police had travel to do so?

• 1] 50 s, 1000 m
• 2] 65 s, 1150 m
• 3] 65 s, 1300 m
• 4] 45 s, 1050 m
• 5] None of these

Walking at the rate of 4 km an hour, a man cover a certain distance in 3 hours 45 minutes. If he covers the same distance on cycle, cycling at the rate of 16.5 km/hour, the time taken by him is :

• 1] 55.45 minutes
• 2] 54.55 minutes
• 3] 55.44 minutes
• 4] 45.55 minutes

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

A person crosses a 600 m long street in 5 minutes. What is his speed in km per hour?

• 1] 3.6 km/hr
• 2] 7.2 km/hr
• 3] 8.4 km/hr
• 4] 10 km/hr

A can give 40 metres start to B and 70 metres to C in a race of one kilometre how many metres starts can B give to C in a race of one kilometre ?

• 1]

  30 metres

• 2]

  \(\frac{700}{29}\) metres

• 3]

  \(31\frac{1}{4}\) metres

• 4]

  32 metres

Sabarmati express takes 18 seconds to pass completely through a station 162 m long and 15 seconds through another station 120 m long. The length of the train is :

• 1] 132 m
• 2] 100 m
• 3] 80 m
• 4] 90 m

Amit starts from a point A and walks to another points B and then returns from B to A by his car and thus takes a total time of 6 hours and 45 min. If he had driven both ways in his car, he would have taken 2 hours less. How long would it take for him to walk both ways ?

• 1] 7 hrs 45 min
• 2] 8 hrs 15 min
• 3] 8 hrs 30 min
• 4] 8 hrs 45 min

A and B start from the same point and in the same direction at 7 am to walk around a rectangular field 400 m × 300 m. A and B walk at the rate of 3 km/hr and 2.5 km/hr respectively. How many times shall they cross each other if they continue to walk till 12.30 pm ?

• 1] Not even once
• 2] Once
• 3] Twice
• 4] Thrice