A rower whose speed is 2.5 km/hr in still water rows to a certain point upstream and back to the starting point in a river which flows at 0.5 km/hr. What is the rower's average speed (in km/hr) for the total journey?
Choose the correct option.
A) 2.2	B) 2.3	C) 2.4	D) 2.5	E) 2.6
time upstream = d / 2   time downstream = d / 3   total time = d/2 + d/3 = 5d/6   average speed = 2d / (5d/6) = 2.4 km/hr   The answer is 2.4.2  / (5 /6)= 
<gadget id="calculator">2  / (5 /6)</gadget>
<output>12/5 = around 2.4</output>
2.4 km/hr   The answer is 2.4.
<result>C</result>
A rower whose speed is 2.5 km/hr in still water rows to a certain point upstream and back to the starting point in a river which flows at 0.5 km/hr. What is the rower's average speed (in km/hr) for the total journey?