Quiz Discussion

A train covers a distance of 10 km in 12 minutes. If its speed is decreased by 5 km/hr, the time taken by it to cover the same distance will be :

• 1]

  10 minutes

• 2]

  13 minutes 20 seconds

• 3]

  13 minutes

• 4]

  11 minutes 20 seconds

A student goes to school at the rate of \(2\frac{1}{2}\) km/hr and reaches 6 min late. If he travels at the speed of 3 km/hr he is 10 min early. What is the distance to the school?

• 1]

  4 km

• 2]

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

• 3]

  1 km

• 4]

  \(3\frac{1}{2}\) km

A ship, 40 kilometers from the shore, springs a leak which admits \(3\frac{3}{4}\) tonnes of water in 12 minutes. 60 tonnes would suffice to sink her, but the ship's pumps can throw out 12 tonnes of water in one hour. Find the average rate of sailing, so that she may reach the shore just as she begging to sink?

• 1]

  \(1\frac{1}{2}\) km/hr

• 2]

  \(2\frac{1}{2}\) km/hr

• 3]

  \(3\frac{1}{2}\) km/hr

• 4]

  \(4\frac{1}{2}\) km/hr

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

A man walking at the rate of 5 km/hr crosses a bridge in 15 min. The length of the bridge (in metres) is :

• 1] 600 metres
• 2] 750 metres
• 3] 1000 metres
• 4] 1250 metres

Paschim Express left Delhi for Mumbai at 14.30 hrs travelling at a speed of 60 kmph and August Kranti Express left Delhi for Mumbai in the same day at 16.30 hrs travelling at a speed of 80 kmph. How far away from Delhi will the two trains meet (excluding stoppages) ?

• 1] 120 km
• 2] 360 km
• 3] 480 km
• 4] 500 km

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

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

A man can row 15 km/h in still water and he finds that it takes him twice as much time to row up than as to row down the same distance in the river. The speed of current (in km/h) :

• 1] 6 km/h
• 2] 6.5 km/h
• 3] 4.5 km/h
• 4] 5 km/h

In covering a distance of 30 km, Abhay takes 2 hours more than Sameer. If Abhay doubles his speed, then he would take 1 hour less than Sameer. Abhay's speed is:

• 1] 5 km/hr
• 2] 6 km/hr
• 3] 6.25 km/hr
• 4] 7.5 km/hr