A man rows his boat 90 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?	Choices:
A) 9 kmph  B) 6 kmph  C) 5 kmph  D) 8 kmph  E) 7 kmph
Speed downstream = d/t = 90/(2 1/2) = 36 kmph   Speed upstream = d/t = 45/(2 1/2) = 18 kmph   The speed of the stream = (36 - 18)/2= 
<gadget id="calculator">(36 - 18)/2</gadget>
<output>9</output>
9 kmph   9 kmphnswer:9 kmph
<result>A</result>
A man rows his boat 90 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?