Question

A man can row at $8$ kmph in still water. If the river is running at $2$ kmph, it takes him $48$ minutes to row to a place and back. How far is the place?

• A. $1$ km
• B. $2$ km
• C. $3$ km
• D. $4$ km

Answer 1

Answer: (C)

$3$ km

Speed of the man in still water $=8$ kmph.
Speed of the river $=2$ kmph
Downstream $=8+2=10$ kmph
Upstream $=8-2=6$ kmph
$\Rightarrow \frac{x}{10}+\frac{x}{6}=\frac{48}{60}$
$\Rightarrow 8x=24$
$\Rightarrow x=3$ km