document.write( "Question 807785: if a bird flies 40km/h with the wind,but only 10km/h against the wind , what is the rate of bird in still air? what is the rate of wind? \n" ); document.write( "
Algebra.Com's Answer #486523 by josmiceli(19441)\"\" \"About 
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Let \"+w+\" = the rate of the wind
\n" ); document.write( "Let \"+b+\" = the rate of the bird in still air
\n" ); document.write( "-----------------------
\n" ); document.write( "Going with the wind:
\n" ); document.write( "\"+b+%2B+w+=+40+\" km/hr
\n" ); document.write( "Going against the wind:
\n" ); document.write( "\"+b+-+w+=+10+\" km/hr
\n" ); document.write( "--------------------
\n" ); document.write( "Add the equations
\n" ); document.write( "\"+2b+-+50+\"
\n" ); document.write( "\"+b+=+25+\"
\n" ); document.write( "and
\n" ); document.write( "\"+b+%2B+w+=+40+\"
\n" ); document.write( "\"+25+%2B+w+=+40+\"
\n" ); document.write( "\"+w+=+15+\"
\n" ); document.write( "------------
\n" ); document.write( "The rate of the wind is 15 km/hr
\n" ); document.write( "The rate of the bird in still air is 25 km/hr
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