You drive 125 miles in 3 hours. How long will it take you to drive 400 miles if you go the same rate?

125 miles / 3 hours = 400 miles / x hours

( 125/3)x = 400
x = 1200 /125 = 9.6 hours = 9 hours 36 minutes
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CHECK
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9.6 hours * 125 miles /3 hours = 400 miles sure enough