Quiz Discussion

In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:

• 1] 3 kmph
• 2] 5 kmph
• 3] 8 kmph
• 4] 9 kmphr

On a river , Q is the mid - point between two points P and R on the same bank of the river. A boat can go from P to Q and back in 12 hours, and from P to R in 16 hours 40 minutes. How long would it take to go from R to P?

• 1]

  \({ \text{3}}\frac{3}{7}\) hr

• 2]

  5 hr

• 3]

  \({ \text{6}}\frac{2}{3}\) hr

• 4]

  \({ \text{7}}\frac{1}{3}\) 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 man rows 12 km in 5 hours against the stream and the speed of current being 4 kmph. What time will be taken by him to row 15 km with the stream?

• 1]

  1 hour \({ \text{27}}\frac{7}{{13}}\) minutes

• 2]

  1 hour \({ \text{24}}\frac{7}{{13}}\) minutes

• 3]

  1 hour \({ \text{25}}\frac{7}{{13}}\) minutes

• 4]

  1 hour \({ \text{26}}\frac{7}{{13}}\) minutes

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 covers 24 km upstream and 36 km downstream in 6 hours, while it covers 36 km upstream and 24 km downstream in \(6\frac{1}{2}\) hours. The speed of the current is?

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

Speed of a boat in standing water is 9 kmph and the speed of the stream is 1.5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. The total time taken by him is:

• 1] 16 hours
• 2] 18 hours
• 3] 20 hours
• 4] 24 hours

A boat takes half time in moving a certain distance downstream than upstream. The ratio of the speed of the boat in still water and that of the current is?

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

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

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