I was running better than 10 minutes per mile .
Whenever I did n't know the distance ( this was 40 years ago before GPS ) I 'd just divide the time by 10 and use that result as my distance .
I was running better than 10 minutes per mile , so whenever I did n't know the distance ( this was 40 years ago before GPS ) I 'd just divide the time by 10 and use that result as my distance .