document.write( "Question 1136644: An airplane encountered a head wind during a flight between Joppetown and Jawsburgh, which took 4 hours and 42 minutes. The return flight took 4 hours. If the distance from Joppetown to Jawsburgh is 1400 miles, find the airspeed of the plane (the speed of the plane in still air) and the speed of the wind, assuming both remain constant. \n" ); document.write( "

Algebra.Com's Answer #754442 by ikleyn(52946) $\"\"$ $\"About$

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document.write( "Let u be the airspeed of the airplane (in miles per hour), and\r\n" );
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document.write( "let v be the speed of the wind.\r\n" );
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document.write( "The speed of the airplane flying with the wind is (u + v); at the same time it is equal to  \r\n" );
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document.write( "     = 350 miles per hour.\r\n" );
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document.write( "So, your first equation is\r\n" );
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document.write( "    u + v = 350.      (1)\r\n" );
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document.write( "The speed of the airplane flying againt the same wind is (u - v); at the same time it is equal to  \r\n" );
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document.write( "     =  =  =  miles per hour.\r\n" );
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document.write( "So, your second equation is\r\n" );
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document.write( "    u - v = .    (2)\r\n" );
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document.write( "Add equations (1) and (2). You will get\r\n" );
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document.write( "    2u =  =  = 647.872  =====>  u =  = 323.936 miles per hour.\r\n" );
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document.write( "Substitute this value of \"u\" into the equation (2) to get v = 350-u = 26.064.\r\n" );
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document.write( "ANSWER.  The airspeed of the plane is  323.936 miles per hour;  the speed of the wind is  26.064 miles per hour.\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is a typical \"tailwind and headwind\" word problem.\r
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\n" ); document.write( "\n" ); document.write( "See the lessons \r
\n" ); document.write( "\n" ); document.write( "    - Wind and Current problems \r
\n" ); document.write( "\n" ); document.write( "    - Wind and Current problems solvable by quadratic equations \r
\n" ); document.write( "\n" ); document.write( "    - Selected problems from the archive on a plane flying with and against the wind \r
\n" ); document.write( "\n" ); document.write( "in this site, where you will find other similar solved problems with detailed explanations.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the section \"Word problems\", the topic \"Travel and Distance problems\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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