A man walks from B to C, a distance of x miles, at 8 miles per hour and returns at 10 miles per hour. What is his average speed?	Choose the most appropriate option:
A) 10 mph
B) 9.6 mph
C) 8.8 mph
D) 8.4 mph
E) 4 mph
Total distance covered = 2x   Time taken12miles / hour = x/10 hrs   Time taken @ 8 miles / hour = x/8 hrs   Avg speed = 2x / (x/8 + x/10) = 8.8 mph   Ans is 8.8 mph
<result>C</result>
A man walks from B to C, a distance of x miles, at 8 miles per hour and returns at 10 miles per hour. What is his average speed?