document.write( "Question 1173837: The rate of a small aircraft in calm air is 125 mph. If the wind is currently blowing south at a rate of 5 mph, how far north can a pilot fly the plane and return it within 4 h? \n" ); document.write( "

Algebra.Com's Answer #799241 by ikleyn(52786) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "            Below I explain how this problem has to be solved, actually.\r
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\n" ); document.write( "\n" ); document.write( "            How it SHOULD be solved and how it is EXPECTED to be solved.\r
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document.write( "It flights WITH  the wind at the effective speed of 125 + 5 = 130 mph\r\n" );
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document.write( "      and AGAINST the wind at the effective speed of 125-5 = 120 mph.\r\n" );
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document.write( "Let \"d\" be this distance, the problem asks for.\r\n" );
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document.write( "Time spent  WITH  the wind  is    hours.\r\n" );
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document.write( "Time spent AGAINST the wind  is    hours.\r\n" );
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document.write( "The total time equation is\r\n" );
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document.write( "     +  = 4 hours   (given).\r\n" );
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document.write( "You just completed the setup, and just have an equation to solve.\r\n" );
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document.write( "To solve it, multiply both sides (everything by 120*130.  You will get\r\n" );
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document.write( "    120d + 130d = 4*120*130,\r\n" );
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document.write( "which gives you\r\n" );
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document.write( "    d =  = 249.6 miles.\r\n" );
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document.write( "ANSWER.   How far North is 249.6 miles.\r\n" );
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\n" ); document.write( "\n" ); document.write( "        You are very happy person, because you got now from me
\n" ); document.write( "        the best possible solution with detailed explanations.\r
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\n" ); document.write( "\n" ); document.write( "        Such a solution with explanations you will get NOWHERE ELSE.\r
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\n" ); document.write( "\n" ); document.write( "Using \"time\" equation is a STANDARD method of solving such problems.\r
\n" ); document.write( "\n" ); document.write( "From this lesson, learn on how to write, how to use and how to solve a \"time\" equation.\r
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\n" ); document.write( "\n" ); document.write( "To see many other similar solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Had a car move faster it would arrive sooner\r
\n" ); document.write( "\n" ); document.write( "    - How far do you live from school? \r
\n" ); document.write( "\n" ); document.write( "    - Earthquake waves \r
\n" ); document.write( "\n" ); document.write( "    - Time equation: HOW TO use, HOW TO write and HOW TO solve it \r
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\n" ); document.write( "\n" ); document.write( "By the way, the solution by @Boreal is formally INCORRECT.\r
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