document.write( "Question 329126: A six passenger airplane cruises at 180 mph in the calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the wind speed? \n" ); document.write( "

Algebra.Com's Answer #235877 by galactus(183) $\"\"$ $\"About$

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The trick to these rate roblems is to read them carefully.\r
\n" ); document.write( "\n" ); document.write( "Note that it says, \"the plane can fly 7 miles with the wind IN THE SAME AMOUNT OF TIME as it can fly 5 miles against the wind\". By the statement, \"in the same amount of time\", it tells use we want to solve d=rt for t=d/r and set one time equal to the other.
\n" ); document.write( "We are asked to find the wind rate, so we know that r must appear in the equation.\r
\n" ); document.write( "\n" ); document.write( "It flies 5 miles against the wind in 5/(180-r) hours.\r
\n" ); document.write( "\n" ); document.write( "It flies 7 miles with the wind in 7/(180+r) hours.\r
\n" ); document.write( "\n" ); document.write( "The problem says these are equal, so we have:\r
\n" ); document.write( "\n" ); document.write( " $\"5%2F%28180-r%29=7%2F%28180%2Br%29\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"r=30\"$ mph for the wind rate. \n" ); document.write( "

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