Answer:
Mr. White can walk 4 miles in 1 hour.
Explanation:
If Mr. White can walk 3 miles in 45 minutes, we can assume that he can walk 1 mile in 15 minutes. From this, we can conclude that Mr. White can walk 4 miles in 1 hour. There are 60 minutes in 1 hour, and 15 goes into 60 four times.
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