Given:
Distance covered, d = 100 yards
Time, t = 9.0 seconds
Let's find the average speed in miles per hour.
To find the average speed, apply the formula:

Since, we are to find the average speed in miles per hour, we are to convert the distance from yards to miles and time from seconds to hours.
We have:
• Distance.
Where:
1 mile = 1760 yards

• Time.
Where:
1 hour = 3600 seconds

The distance in miles is 0.0568 miles.
The time in hours is 0.0025 hour.
Hence, to find the average speed we have:

Therefore, the average speed in miles per hour is 22.72 miles per hour.
ANSWER:
22.72 mph