A cyclist bikes x distance at 8 miles per hour and returns over the same path at 10 miles per hour. What is the cyclist's average rate for the round trip in miles per hour? Choose the correct choice from the following options.
A) 8.1	B) 8.9	C) 8.6	D) 8.3	E) 9.0
Distance = d1 = x miles   Speed = s1 = 8 miles per hour   Time = t1 = Distance/ Speed = x/8   2. Going from B to A   Distance = d2 = x miles   Speed = s2 = 10 miles per hour   Time = t2 = Distance/ Speed = x/10   3. Average Speed = Total Distance/Total Time   Total Distance = x + x = 2x   Total Time = x/10 + x/8 = x (1/10 + 1/8) = =9x/40   Speed = 2x/(9x/40) = 80/9   = 8.9   Answer : 8.9
<result>B</result>
A cyclist bikes x distance at 8 miles per hour and returns over the same path at 10 miles per hour. What is the cyclist's average rate for the round trip in miles per hour?