It takes Joey the postman 1 hours to run a 4 mile long route every day. He delivers packages and then returns to the post office along the same path. If the average speed of the round trip is 5 mile/hour, what is the speed with which Joey returns?	Choose one
A) 6 2/3
B) 12
C) 13
D) 14
E) 15
let his speed for one half of the journey be 4 miles an hour   let the other half be x miles an hour   now,   avg speed =5 mile an hour   2*4*x/4+x=5   8x=5x+20=&gt;3x=20=&gt;x=6 2/3   6 2/3
<result>A</result>
It takes Joey the postman 1 hours to run a 4 mile long route every day. He delivers packages and then returns to the post office along the same path. If the average speed of the round trip is 5 mile/hour, what is the speed with which Joey returns?