Engineering Quantitative Aptitude English Reasoning General Knowledge Coding Others

Quiz: Boats and Streams

To View Tricks: Login Required

Number of Questions: 40

Question: 6 -

A man can row his boat with the stream at 6 km/h and against the stream in 4 km/h. The man's rate is? 

Options:

  1. 8

  2. 1

  3. 3

  4. 5

    5. Answer:

    1
    Solution:

    DS = 6

    US = 4

       S = ?

    S = (6 - 4)/2 = 1 kmph

Question: 7 -

A man can row with a speed of 15 kmph in still water. If the stream flows at 5 kmph, then the speed in downstream is? 

Options:

  1. 5

  2. 10

  3. 22

  4. 20

    5. Answer:

    20
    Solution:

    M = 15

    S = 5

    DS = 15 + 5 = 20

Question: 8 -

A man can swim in still water at 4.5 km/h, but takes twice as long to swim upstream than downstream. The speed of the stream is? 

Options:

  1. 7.5

  2. 1.5

  3. 2.25

  4. 3

    5. Answer:

    1.5
    Solution:

    M = 4.5

    S = x

    DS = 4.5 + x

    US = 4.5 + x

    4.5 + x = (4.5 - x)2

    4.5 + x = 9 -2x

    3x = 4.5

    x = 1.5

Question: 9 -

A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 10 minutes. How long will it take to go 5 km in stationary water? 

Options:

  1. 1 hour

  2. 40 minutes

  3. 1 hr 15 min

  4. 1 hr 30 min

    5. Answer:

    1 hr 15 min
    Solution:

    Rate downstream = 1 x 60 km/hr = 6 km/hr.
    10

    Rate upstream = 2 km/hr.

    Speed in still water = 1 (6 + 2) km/hr = 4 km/hr.
    2
    Required time = 5/4 hrs = 1 1 hrs = 1 hr 15 min.

Question: 10 -

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: 

Options:

  1. 16 hours

  2. 18 hours

  3. 20 hours

  4. 24 hours

    5. Answer:

    24 hours
    Solution:

    Speed upstream = 7.5 kmph.

    Speed downstream = 10.5 kmph.

     Total time taken = 105 + 105 hours = 24 hours.
    7.5 10.5