You run the first mile at 10 miles per hour and the second m

You run the first mile at 10 miles per hour, and the second mile at 8 miles per hour. How many miles per hour is your average speed for the two-mile run?

Solution

Time taken in running first mile is t1 = distance/speed

t1 = 1/10 = 0.1 hr

Time taken in running second mile is t2 = distance/speed

t2=1/8 = 0.125 hr

Total distance = 1 mile + 1 mile = 2mile

Total time = 0.1 + 0.125 = 0.225 hrs

So, average speed = total distance / total time

average speed = 2/0.225

average speed =8.89 miles per hous