Quiz Discussion

Each wheel of a car is making 5 revolutions per second. If the diameter of a wheel is 84 cm, then the speed of the car in cm/sec would be :

• 1] 420 cm/sec
• 2] 264 cm/sec
• 3] 1000 cm/sec
• 4] 1320 cm/sec

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 girl while walking diametrically across a semicircular playground, takes 3 minutes less than if she had kept walking round the circular path from A to B. If she walks 60 metres a minute, what is diameter of the play ground?

• 1] 60 m
• 2] 48 m
• 3] 84 m
• 4] 315 m
• 5] None of these

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 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

Train A travelling at 60 km/hr leaves Mumbai for Delhi at 6 pm. Train B travelling at 90 km/hr also leaves Mumbai for Delhi at 9 pm. Train C leaves Delhi for Mumbai at 9 pm. If all the three trains meet at the same time between Mumbai and Delhi, then what is the speed of train C if the distance between Delhi and Mumbai is 1260 km ?

• 1] 60 km/hr
• 2] 90 km/hr
• 3] 120 km/hr
• 4] 135 km/hr

A train 300 m long passed a man walking along the line in the same direction at the rate of 3 km/hr in 33 sec. The speed of the train is :

• 1]

  30 km/hr

• 2]

  32 km/hr

• 3]

  \(32\frac{8}{{11}}\)  km/hr

• 4]

  \(35\frac{8}{{11}}\)  km/hr

A motor boat takes 2 hours to travel a distance of 9 km downstream and it takes 6 hours to travel the same distance against the current. The speed of the boat in still water and that of the current (in km/h) respectively are:

• 1] 6, 5 km/h
• 2] 3, 1.5 km/h
• 3] 8, 5 km/h
• 4] 9, 3 km/h

An ant climbing up a vertical pole ascends 12 meters and slips down 5 meters in every alternate hour. If the pole is 63 meters high how long will it take it to reach the top?

• 1] 18 hours
• 2] 17 hours
• 3] 16 hours 35 min
• 4] 16 hours 40 min
• 5] None of these

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