How To Make Money Bicycling

Can i get help on this physics problem?

Fred is riding his bike in a race to earn money for a sick boy. Fred rides his bicycle at a top speed of 17miles/hour. If Fred gets a dollar for every mile he rides in a time period of 4 hours, how much money will he make for the sick boy?

Fred makes 17miles each hour of his ride. For four hours he makes 17miles X 4 = 68 miles.
One dollar for every mile, then he gets $68.
Not much for the poor sick boy!

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