A marathon runner completed a race of 26.2 miles in 3 hours and 15 minutes. What was his average speed throughout the race? a) 7.5
b) 8.1
c) 8.7
d) 10

b

Explanation:

The average speed of an object is the sum of the distance traveled by the object relative to the total time taken to cover the distance. In other words,

Average speed = total distance traveled/total time taken

In this case, the total distance traveled by the runner = 26.2 miles while the total time taken = 3 hours and 15 minutes

60 minutes = 1 hour

15 minutes = 0.25 hours, hence

3 hours 15 minutes = 3.25 hours

Average speed = 26.2/3.25

                          = 8.0615 miles/hour

                            = 8.1 miles/hour

The correct option is b.