Quiz Discussion

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

Two trains 150 m and 120 m long respectively moving from opposite direction cross each other in 10 sec. If the speed of the second train is 43.2 km/hr, then the speed of the first train is :

• 1] 54 km/hr
• 2] 50 km/hr
• 3] 52 km/hr
• 4] 51 km/hr

Deepa rides her bike at an average speed of 30 km/hr and reaches her destination in 6 hours. Hema covers the same distance in 4 hours. If Deepa increases her average speed by 10 km/hr and Hema increases her average speed by 5 km/hr, what would be the difference in their time taken to reach the destination ?

• 1] 40 min
• 2] 45 min
• 3] 54 min
• 4] 1 hr
• 5] None of these

The speed of a bus is 72 kmph. The distance covered by the bus in 5 sec is :

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

A thief is noticed by a policeman from a distance of 200 m. The thief starts running and the policeman chases him. The thief and the policeman run at the rate of 10 km and 11 km per hour respectively. What is the distance between them after 6 minutes ?

• 1] 100 m
• 2] 150 m
• 3] 190 m
• 4] 200 m

A postman goes with a speed of 36 km/h what is the speed of postman in m/s?

• 1] 4.5 m/s
• 2] 6 m/s
• 3] 5 m/s
• 4] 10 m/s

A person can row a boat d km upstream and the same distance downstream in 5 hours 15 minutes. Also, he can row the boat 2d km upstream in 7 hours. How long will it take to row the same distance 2d km downstream?

• 1]

  \(\frac{{3}}{{2}}\) hours

• 2]

  7 hours

• 3]

  \(\frac{{29}}{{4}}\) hours

• 4]

  \(\frac{{7}}{{2}}\) hours

A runs twice as fast as B and B runs thrice as fast as C. The distance covered by C in 72 minutes, will be covered by A in:

• 1] 18 minutes
• 2] 24 minutes
• 3] 16 minutes
• 4] 12 minutes

A distance of 425 km separates two trains moving towards each other at a speed of 200 km/hr each. What will be the distance between them after 1 hr 30 min, if they reduce their speed by half, every half an hour ?

• 1] 75 km
• 2] 120 km
• 3] 150 km
• 4] 200 km

A salesman travels a distance of 50 km in 2 hours and 30 minutes. How much faster, in kilometres per hour, n a n average must he travel to make such a trip in 5656 hour less time?

• 1]

  10

• 2]

  20

• 3]

  30

• 4]

  None Of these