LR Exam > LR Questions > A boat takes 90 minutes less to travel 36 mil...
Start Learning for Free
A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
- a)4 mph
- b)2.5 mph
- c)3 mph
- d)2 mph
Correct answer is option 'D'. Can you explain this answer?
| FREE This question is part of | Download PDF Attempt this Test |
Verified Answer
A boat takes 90 minutes less to travel 36 miles downstream than to tra...
Most Upvoted Answer
A boat takes 90 minutes less to travel 36 miles downstream than to tra...
Given:
- Distance = 36 miles
- Speed of boat in still water = 10 mph
To find:
- Speed of the stream
Let's assume the speed of the stream is 'x' mph.
Speed downstream:
When the boat is moving downstream, it gets the additional speed from the stream, so the effective speed becomes (10 + x) mph.
Speed upstream:
When the boat is moving upstream, it has to fight against the stream, so the effective speed becomes (10 - x) mph.
Time taken:
We are given that the boat takes 90 minutes less to travel downstream compared to upstream.
Let's calculate the time taken to travel downstream and upstream.
Time downstream:
Distance = Speed × Time
36 = (10 + x) × Time downstream
Time upstream:
Distance = Speed × Time
36 = (10 - x) × Time upstream
We are given that the time taken downstream is 90 minutes less than the time taken upstream. We can convert 90 minutes into hours by dividing it by 60.
Time downstream = Time upstream - 90/60
Time downstream = Time upstream - 1.5
Substituting the values of time downstream and time upstream into the equations:
36 = (10 + x) × (Time upstream - 1.5)
36 = (10 - x) × Time upstream
Simplifying the equations:
10Time upstream - 1.5(10 + x) = 36
10Time upstream - 10x = 36
10Time upstream - 1.5(10 - x) = 36
10Time upstream + 1.5x = 36
Solving the two equations simultaneously:
10Time upstream - 1.5(10 + x) = 36
10Time upstream - 1.5(10 - x) = 36
10Time upstream - 15 - 1.5x = 36
10Time upstream + 15 + 1.5x = 36
Combining like terms:
10Time upstream - 1.5x = 51
10Time upstream + 1.5x = 21
Adding the two equations:
20Time upstream = 72
Time upstream = 3.6 hours
Substituting the value of Time upstream into one of the original equations:
10Time upstream + 1.5x = 21
10(3.6) + 1.5x = 21
36 + 1.5x = 21
1.5x = 21 - 36
1.5x = -15
x = -15/1.5
x = -10
Since the speed of the stream cannot be negative, we discard the negative value of x.
Therefore, the speed of the stream is 2 mph. (Option D)
- Distance = 36 miles
- Speed of boat in still water = 10 mph
To find:
- Speed of the stream
Let's assume the speed of the stream is 'x' mph.
Speed downstream:
When the boat is moving downstream, it gets the additional speed from the stream, so the effective speed becomes (10 + x) mph.
Speed upstream:
When the boat is moving upstream, it has to fight against the stream, so the effective speed becomes (10 - x) mph.
Time taken:
We are given that the boat takes 90 minutes less to travel downstream compared to upstream.
Let's calculate the time taken to travel downstream and upstream.
Time downstream:
Distance = Speed × Time
36 = (10 + x) × Time downstream
Time upstream:
Distance = Speed × Time
36 = (10 - x) × Time upstream
We are given that the time taken downstream is 90 minutes less than the time taken upstream. We can convert 90 minutes into hours by dividing it by 60.
Time downstream = Time upstream - 90/60
Time downstream = Time upstream - 1.5
Substituting the values of time downstream and time upstream into the equations:
36 = (10 + x) × (Time upstream - 1.5)
36 = (10 - x) × Time upstream
Simplifying the equations:
10Time upstream - 1.5(10 + x) = 36
10Time upstream - 10x = 36
10Time upstream - 1.5(10 - x) = 36
10Time upstream + 1.5x = 36
Solving the two equations simultaneously:
10Time upstream - 1.5(10 + x) = 36
10Time upstream - 1.5(10 - x) = 36
10Time upstream - 15 - 1.5x = 36
10Time upstream + 15 + 1.5x = 36
Combining like terms:
10Time upstream - 1.5x = 51
10Time upstream + 1.5x = 21
Adding the two equations:
20Time upstream = 72
Time upstream = 3.6 hours
Substituting the value of Time upstream into one of the original equations:
10Time upstream + 1.5x = 21
10(3.6) + 1.5x = 21
36 + 1.5x = 21
1.5x = 21 - 36
1.5x = -15
x = -15/1.5
x = -10
Since the speed of the stream cannot be negative, we discard the negative value of x.
Therefore, the speed of the stream is 2 mph. (Option D)
|
Explore Courses for LR exam
|
|
Similar LR Doubts
A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer?
Question Description
A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is: a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? for LR 2024 is part of LR preparation. The Question and answers have been prepared according to the LR exam syllabus. Information about A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is: a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for LR 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is: a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer?.
A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is: a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? for LR 2024 is part of LR preparation. The Question and answers have been prepared according to the LR exam syllabus. Information about A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is: a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for LR 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is: a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer?.
Solutions for A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for LR.
Download more important topics, notes, lectures and mock test series for LR Exam by signing up for free.
Here you can find the meaning of A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice A boat takes 90 minutes less to travel 36 miles downstream than to travel the same distance upstream. If the speed of the boat in still water is 10 mph, the speed of the stream is:
a)4 mphb)2.5 mphc)3 mphd)2 mphCorrect answer is option 'D'. Can you explain this answer? tests, examples and also practice LR tests.
|
|
Explore Courses for LR exam
|
|
Suggested Free Tests
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up
within 7 days!
within 7 days!
Takes less than 10 seconds to signup