When using the Speed= distance/time how would one go about plugging numbers in if the question in a wheel has the diameter of 7 and rotates 1700 revolution per minute. I know you use the Circunfrace which is 14pie then what do you do about the 1700 revolutions; where does that fit in? If any one can give me a clear cut answer about this and similar problems it would be greatly apprecitated.