A man's speed with the current is 17.5 km / hr and the speed of the current is3.5 km / hr. The man's speed against the current is  Choose the correct choice from the following answers:  A) 8.5 km / hr  B) 9 km / hr  C) 10 km / hr  D) 11.5 km / hr  E) None
Sol.   Man's rate in still in water = (17.5 - 3.5) km / hr = 14 km / hr.   Man's rate against the current = (14 - 3.5) km / hr = 11.5 km / hr.   Answer 11.5 km / hr
<result>D</result>
A man's speed with the current is 17.5 km / hr and the speed of the current is3.5 km / hr. The man's speed against the current is