document.write( "Question 1101214: On Sunday morning, Mr. Howard flew a plane from his hometown to Dallas,flying at an average speed of 468 miles per hour. Later that day, hew flew the plane back to his hometown. Together, the two flights lasted a total of 11 hours. If Mr. Howard flew at an average speed of 390 miles per hour on the return trip, how long did the return trip take?\r
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Algebra.Com's Answer #715759 by ikleyn(52830) $\"\"$ $\"About$

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document.write( "Let \"T\" be the time (in hours) for the returning trip, which is under the question.\r\n" );
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document.write( "Then the time for the flight to Dallas was (11-T) hours.\r\n" );
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document.write( "We have two distances equal:\r\n" );
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document.write( "468*(11-T) = 390*T.   ====>\r\n" );
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document.write( "5148 - 468T = 390T  ====>  5148 = 390T + 468T  ====>  5148 = 858T  ====>  T =  = 6.\r\n" );
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document.write( "Answer.  6 hours. Option B).\r\n" );
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