Question : A boat running upstream takes 10 hours to cover a certain distance, while it takes 7 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and that of the water current, respectively?
Option 1: 17 : 5
Option 2: 3 : 17
Option 3: 2 : 17
Option 4: 17 : 3
Latest: SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL complete guide
Correct Answer: 17 : 3
Solution :
Given:
Time to cover the distance upstream = 10 hr
Time to cover the distance downstream = 7 hr
Speed of boat downstream = Speed of boat in still water + speed of current
Speed of boat upstream = Speed of boat in still water – speed of current
Distance = Speed $\times$ Time
Let the speed of the boat in still water be $x$ km/h and the speed of the stream of water be $y$ km/h.
According to the question,
$\frac{\text{Upstream Speed}}{\text{Downstream Speed}} = \frac{7}{10}$
⇒ $\frac{x - y}{x + y} = \frac{7}{10}$
⇒ $(x+y)\times7 = (x-y)\times10$
⇒ $7x + 7y = 10x - 10y$
⇒ $3x = 17y$
⇒ $ \ \frac{x}{y} = \frac{17}{3}$
$\therefore x:y=17:3$
Hence, the correct answer is 17 : 3.
Related Questions
Know More about
Staff Selection Commission Combined Grad ...
Answer Key | Eligibility | Application | Selection Process | Preparation Tips | Result | Admit Card
Get Updates Brochure
Your Staff Selection Commission Combined Graduate Level Exam brochure has been successfully mailed to your registered email id “”.
