document.write( "Question 1110174: 2 airplanes start at the same place and fly in opposite directions. The average rate of one plane is 18 miles per hour faster than the other one. Find the rate of each plane if they are 1179 miles apart after 1 1/2 hours. \n" ); document.write( "

Algebra.Com's Answer #725162 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Distance by the 1-st airplane + Distance by the 2-nd airplane = 1179 miles.\r\n" );
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document.write( "                             +                  = 1179     ( =  hours =  hours)\r\n" );
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document.write( "Multiply both sides by 2:\r\n" );
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document.write( "3r + 3*(r+18) = 1179*2\r\n" );
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document.write( "3r + 3r + 54 = 2358\r\n" );
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document.write( "6r = 2358 - 54 = 2304  ====>  r =  = 384 miles per hour.\r\n" );
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document.write( "Answer.  The slower airplane speed is 384 mph.\r\n" );
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document.write( "         The faster is 384 + 18 = 402 mph.\r\n" );
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\n" ); document.write( "On introductory lessons on Travel and Distance problems see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Travel and Distance problems \r
\n" ); document.write( "\n" ); document.write( "    - Travel and Distance problems for two bodies moving in opposite directions \r
\n" ); document.write( "\n" ); document.write( "    - Travel and Distance problems for two bodies moving in the same direction (catching up)\r
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