What is the speed of the stream if a canoe rows upstream at 6km/hr and downstream at 12km/hr  Choose the most appropriate option.
A) 1 kmph B) 4 kmph C) 3 kmph D) 2 kmph E) 1.9 kmph
Sol.   Speed of stream = 1/2(12 -6) kmph = 3 kmph.   Answer 3 kmph
<result>C</result>
What is the speed of the stream if a canoe rows upstream at 6km/hr and downstream at 12km/hr