Question

A man can row at 5kmph in still water. If the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back, how far is the place?

• A. 2.4 km
• B. 2.6 km
• C. 3 km
• D. 3.6 km

Answer 1

The correct option is A 2.4 km

Speed downstream = (5 +1) kmph = 6 kmph
Speed upstream = (5 - 1)kmph = 4 kmph
Let the required distance be x km
Then $\frac{x}{6}$ + $\frac{x}{4}$ = 1
$\Rightarrow$ 2x + 3x = 12
$\Rightarrow$ 5x = 12
$\Rightarrow$ x = 2.4 km.