A man rows his boat 75 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream? Choose one: A) 5 kmph B) 6 kmph C) 9 kmph D) 8 kmph E) 1 kmph
Speed downstream = d/t = 75/(2 1/2) = 30 kmph   Speed upstream = d/t = 45/(2 1/2) = 18 kmph   The speed of the stream = (30 - 18)/2= 
<gadget id="calculator">(30 - 18)/2</gadget>
<output>6</output>
6 kmph   Answer:6 kmph
<result>B</result>
A man rows his boat 75 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?