document.write( "Question 571025: So I had a kinda hard test today...well it was easy until this hard head wind/tail wind problem came up. The problem went like this Johnny went head wind (east to west I believe) from Miami to San Francisco 2100 miles at 5.6 lies per hour. When this other person (a girl) went tail wind (west to east) from San Francisco to Miami 2100 miles too but only took 4.8 miles per hour...what is the air speed and the wind speed?\r
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Algebra.Com's Answer #367935 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!
So I had a kinda hard test today...well it was easy until this hard head wind/tail wind problem came up. The problem went like this Johnny went head wind (east to west I believe) from Miami to San Francisco 2100 miles at 5.6 lies per hour. When this other person (a girl) went tail wind (west to east) from San Francisco to Miami 2100 miles too but only took 4.8 miles per hour...what is the air speed and the wind speed?
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document.write( "The way you have it doesn't make sense.  All the planes I've seen fly a little\r\n" );
document.write( "faster than 4.8 miles per hour, because you can walk that fast.\r\n" );
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document.write( "Here's a way it could have been:\r\n" );
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document.write( "Johnny flew 2100 miles Miami to SF against the wind while his girl friend flew\r\n" );
document.write( "from SF to Miama with the wind in 4.8 hours.  They communicated by cell phone\r\n" );
document.write( "and kept their air speed indicators exactly the same speed the whole way. It\r\n" );
document.write( "took him 5.6 hours and her 4.8 hours. \r\n" );
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document.write( "x = air speed (how fast they would be going if the air was still.\r\n" );
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document.write( "         distance    rate      time\r\n" );
document.write( "Johnny     2100      x-w       5.6 \r\n" );
document.write( "girl       2100      x+w       4.8\r\n" );
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document.write( "           2100 = (x-w)5.6\r\n" );
document.write( "           2100 = (x+w)4.8\r\n" );
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document.write( "Multiply the first by 5.6 and the second by 4.8\r\n" );
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document.write( "            375   = x - w\r\n" );
document.write( "            437.5 = x + w\r\n" );
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document.write( "Add the equations get \r\n" );
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document.write( "           812.5 = 2x\r\n" );
document.write( "          406.25 = x\r\n" );
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document.write( "Multiply the first by -1 and add\r\n" );
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document.write( "            -375  = -x + w\r\n" );
document.write( "            437.5 =  x + w\r\n" );
document.write( "             52.5 =     2w\r\n" );
document.write( "            25.25 = w\r\n" );
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document.write( "So the airspeed they kept their planes at was 406.25 mph and\r\n" );
document.write( "the wind was blowing 25.25 miles per hour toward the west.\r\n" );
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document.write( "That's probably not the way it was stated but at least that\r\n" );
document.write( "makes a little more sense.\r\n" );
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document.write( "Edwin

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