A motor cyclist participant of a race says "We drove with the speed of 10 miles an hour one way, but while returning because of less traffic we drove on the same route with 20 miles per hour." What was their average speed in the whole journey?
Choose the correct choice from the following choices
A) 13.3 miles/hour
B) 12 miles/hour
C) 11 miles/hour
D) 13 miles/hour
E) 14 miles/hour
2xy/x+y=13.3 miles/hour   13.3 miles/hourNSWER:13.3 miles/hour
<result>A</result>
A motor cyclist participant of a race says "We drove with the speed of 10 miles an hour one way, but while returning because of less traffic we drove on the same route with 20 miles per hour." What was their average speed in the whole journey?