Quiz Discussion

A motorboat, whose speed in 15 km/hr in still water goes 30 km downstream and comes back in a total of 4 hours 30 minutes. The speed of the stream (in km/hr) is:

• 1] 4 km/hr
• 2] 5 km/hr
• 3] 6 km/hr
• 4] 10 km/hr

The speed of a boat in still water in 15 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 12 minutes is:

• 1] 1.2 km
• 2] 1.8 km
• 3] 2.4 km
• 4] 3.6 km
• 5] None of these

A man's speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man's speed against the current is:

• 1]

  8.5 km/hr

• 2]

  9 km/hr

• 3]

  10 km/hr

• 4]

  12.5 km/hr

A boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream.

• 1] 2 hours
• 2] 3 hours
• 3] 4 hours
• 4] 5 hours
• 5] None of these

A man can row at a speed of \(4\frac{1}{2}\) km/hr in still water. If he takes 2 times as long to row a distance upstream as to row the same distance downstream, then the speed of stream (in km/hr) is-

• 1] 1
• 2] 1.5
• 3] 2
• 4] 2.5

A boat running upstream takes 8 hours 48 minutes to cover a certain distance, while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and speed of the water current respectively?

• 1] 2 : 1
• 2] 3 : 2
• 3] 8 : 3
• 4] Cannot be determined
• 5] None of these

A boat while dowenstream in a reiver converd a distance of 50 miles at an average speed of 60 miles per hour. While returning , because of the water resistance , it took 1 hour 15 minutes to cover the same distance What was the average speed during the whole journey?

• 1] 40 mph
• 2] 48 mph
• 3] 50 mph
• 4] 55 mph

A man can row 6 km/hr in still water. If the speed of the current is 2 km/hr he takes 4 hours more in upstream than the downstream. The distance is?

• 1] 30 km
• 2] 24 km
• 3] 20 km
• 4] 32 km

A man can row at 5 kmph in still water. If the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back, how far is the place?

• 1] 2.4 km
• 2] 2.5 km
• 3] 3 km
• 4] 3.6 km
• 5] None of these

A boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream.

• 1]

  2 hours

• 2]

  3 hours

• 3]

  4 hours 

• 4]

  5 hours