



 
Hi Joi, The paddle wheel in the river functions like a wheel rolling on a road. The radius of the paddle wheel is 4 feet so its circumference is 2 π r = 2 × π × 4 = 251.33 feet. Since the wheel makes 10 revolutions per minute a point on the circumference of the paddle wheel travels 10 × 251.33 = 2513.3 feet each minute. Hence the river is flowing at 2513.3 feet per minute which is 2513.3/5280 = 0.48 miles per hour. Harley  


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