How fast are you really? Time yourself running 100 yards (300 feet) and do the math to figure it out.
How long did it take you (in seconds)?
If you ran 300 feet in that length of time, how many feet would you run in just one second?
Divide 300 by your running time in seconds. Now, how many feet would you run in a minute?
Multiply feet per second by 60. How about a whole hour?
Multiply feet/minute by 60. How fast were you running in miles per hour? Divide the number of feet you would have run in an hour by 5280 (the number of feet in one mile).