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

• 2]

  5

• 3]

  6

• 4]

  10

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 motorboat in still water travels at a speed of 36 km/hr. It goes 56 km upstream in 1 hour 45 monutes. The time taken by it to cover the same distance down the stream will be-

• 1] 1 hour 24 minutes
• 2] 2 hour 21 minutes
• 3] 2 hour 25 minutes
• 4] 3 hour

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

P, Q and R are three towns on a river which flows uniformly. Q is equidistant from P and R. I row from P to Q and back in 10 hours and I can row from P to R in 4 hours. Compare the speed of my boat in still water with that of the river.

• 1] 4 : 3
• 2] 5 : 3
• 3] 6 : 5
• 4] 7 : 3

A man rows to a place 48 km distant and come back in 14 hours. He finds that he can row 4 km with the stream in the same time as 3 km against the stream. The rate of the stream is:

• 1] 1 km/hr
• 2] 1.5 km/hr
• 3] 2 km/hr
• 4] 2.5 km/hr

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 can tarvel 36 km upstream in 5 hours. If the speed of the stream is 2.4 kmph, how much time will the boat take to cover a distance of 78 km downstream?(in hours)

• 1] 5 hours
• 2] 6.5 hours
• 3] 5.5 hours
• 4] 8 hours

Speed of a along and against the current are 14 kms/hr and 8 kms/hr respectively. The speed of the current is?

• 1] 11 km/hr
• 2] 6 km/hr
• 3] 5.5 km/hr
• 4] 3 km/hr

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