It takes Joey the postman 1 hours to run a 3 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 6 mile/hour, what is the speed with which Joey returns?
Select
A) 11 B) 12 C) 13 D) 14 E) 18
let his speed for one half of the journey be 3 miles an hour   let the other half be x miles an hour   now,   avg speed =6 mile an hour   2*3*x/3+x=6   6x=6x+18=&gt;x=18   18
<result>E</result>
It takes Joey the postman 1 hours to run a 3 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 6 mile/hour, what is the speed with which Joey returns?