Question 1101214
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Let "T" be the time (in hours) for the returning trip, which is under the question.

Then the time for the flight to Dallas was (11-T) hours.


We have two distances equal:

468*(11-T) = 390*T.   ====>


5148 - 468T = 390T  ====>  5148 = 390T + 468T  ====>  5148 = 858T  ====>  T = {{{5148/858}}} = 6.


<U>Answer</U>.  6 hours. Option B).
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