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Number of Revolutions
Number of Revolutions  
I have attached a problem about number of revolutions with solution.  Please explain the solution.  Thanks.

The solution shows only the end result, after converting unit. It doesn't show the previous steps in which conversion factors are applied and units canceled out. I think would be clearer if the conversion factors were shown.

"In 1 min, the wheel travels π28n inches"
The missing details:
1 min n rev/min 28π in/rev = 28πn inches

"In 60 min, the wheel travels π28n60 inches"
60 min n rev/min 28π in/rev = 6028πn inches

"i.e. πx28n60/(528012) = 10"
(6028πn inches)/(60 minutes) = 10 mi/hour 5280 ft/mi 12 in/ft 1 hour/(60 minutes) = (10528012 in)/(60 min)
(6028πn) in = 10528012 in
Then they solve for n.  

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