Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Numerical Ability

Topic

Boats and Streams

Question:

The distance between two places A and B is 14 km. A boat travels from A to B downstream and then returns from B to A upstream and takes a total of 3 hours 44 minutes for the entire journey. If the speed of the current is 2 km/h, then what is the speed of the boat, in km/h, in still water?

Options:

$6\frac{1}{2}$

7

8

$7\frac{1}{2}$

Correct Answer:

8

Explanation:

We know that,

Time =  \(\frac{ Distance }{ Speed }\)

Given, = Distance = 14 km

Time taken in upstream and downstream = 3 h 44 min

Speed of current = 2 km/h

Let speed of boat be a km/hr

According to the question =

\(\frac{ 14 }{ a + 2 }\) + \(\frac{ 14 }{ a - 2 }\) = 3 km/hr + 44 min 

With the help of options

If we put a = 8

\(\frac{ 14 }{ 10 }\) + \(\frac{ 14 }{ 6}\) = 1 hr + 24 min + 2 hr + 20 min = 3 hr + 44 min (satisfied)