Question

An olympic sprinter can run 56 yards in 8 seconds. At the same rate, how long (in seconds) would it take the sprinter to run 81 m? Round your answer to one decimal place.

Answer 1

20,365.7 seconds

Explanation:

First, we need to know how to convert yards to miles, as the question is in miles. We know that 1 mile is equivalent to 1760 yards. So we have:

1 mi = 1760 yards

If we multiply both sides by 81:

81 mi = 142,560‬ yards

And we know that the sprinter needs 8 second to run 56 yards:

8 s = 56 yards

If we divide both sides by 56 we get the time he needs for 1 yard:

8/56 s = 56/56 yards

1/7 s = 1 yard

So, takes him 1/7 seconds to run one yard. At this rate he runs 142,560 yards in:

(1/7) * 142,560 = 20,365.7

So, he needs 20,365.7 seconds to run 81 miles (142,560 yards)