8.992254284692088 is the radius I believe
Per means one. So this asks for in one minute, and in one inch.
20 minutes = 6 inches.
So dividing by 20 gets you one minute.
1 minute = 6/20 inches
1 minute = 3/10 inches
20 minutes = 6 inches.
So dividing by 6 gets you one inch.
20/6 minutes = 1 inch
10/3 minutes = 1 inch
