Question 1016512
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When the second brother starts, they 55 miles apart,
and separating at (55mph+65mph=) 120 mph.
They have (230 mi-55 mi=) 175 miles of range left.
175 mi/120 mph=1.46 hours
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ANSWER: They will be in range for 1.46 hours 
after the second brother leaves. 
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