Quiz Discussion

A boat moves downstream at the rate of 1 km in \({ \text{7}}\frac{1}{2}\) minutes and upstream at the rate of 5 km an hour. What is the speed of the boat in the still water?

• 1]

  8 km/hour

• 2]

  \({ \text{6}}\frac{1}{2}\) km/hour

• 3]

  4 km/hour

• 4]

  \({ \text{3}}\frac{1}{2}\) km/hour

A man can row three quarters of a kilometers against the stream in 11 1/4 minutes and return in 7 1/2​ minutes.The speed of the man in still water is

• 1]

  2 km/h

• 2]

  3 km/h

• 3]

  4 km/h

• 4]

  5 km/h

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 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 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 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

There is a road beside a river. Two friends started from a place A moved to a temple situated at another place B and then returned to A again. One of them moves on a cycle at a speed of 12 km/hr, while the other sails at a speed of 10km/hr. If the river flows at a speed of 4km/hr, which of the two friends will return to place A first.

• 1]

  7.4 km/h

• 2]

  8.4 km/h

• 3]

  2.3 km/h

• 4]

  8.6 km/h

a man can row 8 km/hr in still water and he find that it takes thrice as long to row upstream as to row downstream to the same point. What is the speed of the current?

• 1]

  1 kmph

• 2]

  2 kmph

• 3]

  3 kmph

• 4]

  4 kmph

A boat travels 24 km upstream in 6 hours and 20 km downstream in 4 hours. Then the speed of boat in still water and the speed of current are respectively.

• 1] 4 kmph and 3 kmph
• 2] 4.5 kmph and 0.5 kmph
• 3] 4 kmph and 2 kmph
• 4] 5 kmph and 2 kmph