Allen walks at an average speed of 4km/h, to the park and then return to the home he walks at an average speed of 8km/h. Which of the following is the closest approximation of Allen's average speed, in kilometers per hour, for the trip?	Choose one.
A) 8 B) 32 C) 25 D) 16 E) 4
Since we're not given a distance to work with, we can TEST any distance that we like. Here, since the speeds are 4 km/hour and 8 km/hour, using a multiple of both 4 and 8 would make the math easiest.   Let's set the Distance up the hill at 16 km.   So, going park, we have....   D = (R)(T)   16 = (4)(T)   16/4= 
<gadget id="calculator">16/4</gadget>
<output>4</output>
4= T   4 hours to go park   Going home, we have....   16 = (R)(T)   16 = (8)(T)   16/8= 
<gadget id="calculator">16/8</gadget>
<output>2</output>
2= T   2 hours to go home   Total 16istance = 32 km   Total Time = 4+2= 
<gadget id="calculator">4+2</gadget>
<output>6</output>
6 hours   Average Speed= 32/2= 
<gadget id="calculator">32/2</gadget>
<output>16</output>
16 km/hour   16
<result>D</result>
Allen walks at an average speed of 4km/h, to the park and then return to the home he walks at an average speed of 8km/h. Which of the following is the closest approximation of Allen's average speed, in kilometers per hour, for the trip?