Ram can row upstream a boat at 10 km/hr and downstream at 18 km/hr. The rate at which be rows the boat in still water is :

14 km/hr

The correct answer is Option (1) → 14 km/hr

Let the speed of the boat be $x$ km/hr and speed of current be $y$ km/hr.

Upstream speed = $x-y=10\,km/hr$

Downstream speed = $x+y=18\,km/hr$

Add both the equation,

$⇒2x=28$

$⇒x=14\,km/hr$