UPSC Exam  >  UPSC Questions  >  A boat covers a certain distance downstream i... Start Learning for Free
A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?
  • a)
    14 kmph
  • b)
    15 kmph
  • c)
    13 kmph
  • d)
    12 kmph
Correct answer is option 'B'. Can you explain this answer?
Verified Answer
A boat covers a certain distance downstream in 1 hour, while it comes ...
Let the speed of the boat in still water be x kmph. Then,
Speed downstream = (x + 3) kmph,
Speed upstream = (x - 3) kmph.
∴ (x + 3) x 1 = (x - 3) x 3/2
⇒ 2x + 6 = 3x - 9
⇒ x = 15 kmph.
View all questions of this test
Most Upvoted Answer
A boat covers a certain distance downstream in 1 hour, while it comes ...
Let's assume that the speed of the boat in still water is x kmph.

- Downstream Speed:
When the boat is moving downstream, it gets the additional speed of the stream. So, the effective speed of the boat becomes (x + 3) kmph.

Given that the boat covers a certain distance downstream in 1 hour, we can write the equation:
Distance = Speed × Time
Distance downstream = (x + 3) × 1
Distance downstream = x + 3 km

- Upstream Speed:
When the boat is moving upstream, it has to overcome the speed of the stream. So, the effective speed of the boat becomes (x - 3) kmph.

Given that the boat covers the same distance upstream in 112 hours, we can write the equation:
Distance = Speed × Time
Distance upstream = (x - 3) × 112
Distance upstream = 112x - 336 km

- Distance downstream = Distance upstream:
Since the distance covered downstream is the same as the distance covered upstream, we can equate the two distances:
x + 3 = 112x - 336

- Solving the equation:
Let's solve the equation to find the value of x.

112x - x = 336 + 3
111x = 339
x = 339/111
x ≈ 3.054

The speed of the boat in still water is approximately 3.054 kmph.

- Rounding off:
Since the options provided are in whole numbers, we should round off the answer to the nearest whole number. Hence, the speed of the boat in still water is approximately 3 kmph.

- Conclusion:
Therefore, the correct answer is option B) 15 kmph.
Explore Courses for UPSC exam

Top Courses for UPSC

A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer?
Question Description
A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? for UPSC 2024 is part of UPSC preparation. The Question and answers have been prepared according to the UPSC exam syllabus. Information about A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? covers all topics & solutions for UPSC 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer?.
Solutions for A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for UPSC. Download more important topics, notes, lectures and mock test series for UPSC Exam by signing up for free.
Here you can find the meaning of A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer?, a detailed solution for A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? has been provided alongside types of A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice A boat covers a certain distance downstream in 1 hour, while it comes back in 11⁄2 hours. If thespeed of the stream be 3 kmph, what is the speed of the boat in still water?a)14 kmphb)15 kmphc)13 kmphd)12 kmphCorrect answer is option 'B'. Can you explain this answer? tests, examples and also practice UPSC tests.
Explore Courses for UPSC exam

Top Courses for UPSC

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev