document.write( "Question 328411: An airplane took 2.5 hours to fly 625 miles with the wind. It took 4 hours and 10 minutes to make the return trip against the same wind. Find the wind speed and the speed of the plane in still air. (Show all work) \n" ); document.write( "

Algebra.Com's Answer #235244 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
You need 2 equations, one going with the wind
\n" ); document.write( "and one going against the wind
\n" ); document.write( "Let $\"w\"$ = wind speed
\n" ); document.write( "Let $\"a\"$ = speed of plane in still air
\n" ); document.write( "given:
\n" ); document.write( "with the wind:
\n" ); document.write( " $\"t%5B1%5D+=+2.5\"$ hrs
\n" ); document.write( " $\"d+=+625\"$ mi
\n" ); document.write( "against the wind:
\n" ); document.write( " $\"t%5B2%5D+=+4.1667\"$
\n" ); document.write( " $\"d+=+625\"$ mi
\n" ); document.write( "--------------
\n" ); document.write( " $\"625+=+%28a%2Bw%29%2A2.5\"$
\n" ); document.write( " $\"625+=+%28a-w%29%2A4.1667\"$
\n" ); document.write( "This is 2 equations with 2 unknowns, so it's solvable
\n" ); document.write( "(1) $\"625+=+2.5a+%2B+2.5w\"$
\n" ); document.write( "(2) $\"625+=+4.1667a+-+4.1667w\"$
\n" ); document.write( "Multiply both sides of (1) by $\"4.1667%2F2.5\"$
\n" ); document.write( "and add (1) and (2)
\n" ); document.write( "I can't find my calculator, so you can do it
\n" ); document.write( " \n" ); document.write( "

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