Quiz Discussion

A man can row three-quarters of a kilometer against the stream in \(11\frac{1}{4}\) minutes and down the stream in \(7\frac{1}{2}\) minutes. The speed (in km/hr) of the man in still water is:

• 1] 2
• 2] 3
• 3] 4
• 4] 5

The speed of a boat along the stream is 12 km/hr and against the stream is 8 km/hr. The time taken by the boat to sail 24 km in still water is?

• 1] 2 hrs
• 2] 3 hrs
• 3] 2.4 hrs
• 4] 1.2 hrs

A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is:

• 1] 2 : 1
• 2] 3 : 1
• 3] 3 : 2
• 4] 4 : 3

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]

  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

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 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

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

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 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