A man can row upstream at 10kmph and downstream at 20kmph. Find the rate of current ? Choose the correct choice from the following choices:  A) 10km/hr  B) 15km/hr  C) 20km/hr  D) 5km/hr  E) 3km/hr
Rate of current = 1/2 (20-10) = 5km/hr   Answer is 5km/hr
<result>D</result>
A man can row upstream at 10kmph and downstream at 20kmph. Find the rate of current ?