document.write( "Question 225880: I need help with this problem:\r
\n" ); document.write( "\n" ); document.write( "With a certain tail wind a certain jet aircraft arrives at it's destination, 1,890 miles away,in 3 hours. Flying against the same wind, the plane makes the return trip in 3 3/8 hours. Find the wind speed and the plane's airspeed.\r
\n" ); document.write( "\n" ); document.write( "thank's
\n" ); document.write( "Destiny \n" ); document.write( "
Algebra.Com's Answer #168442 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
With a certain tail wind a certain jet aircraft arrives at it's destination, 1,890 miles away,in 3 hours.
\n" ); document.write( " Flying against the same wind, the plane makes the return trip in 3 3/8 hours.
\n" ); document.write( " Find the wind speed and the plane's airspeed.
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\n" ); document.write( "Let s = speed of the plane in still air
\n" ); document.write( "Let w = speed of the wind
\n" ); document.write( "then
\n" ); document.write( "(s-w) = plane speed against the wind
\n" ); document.write( "and
\n" ); document.write( "(s+w) = plane speed with the wind
\n" ); document.write( ":
\n" ); document.write( "Change 3 3/8 hrs to 3.375 hrs
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\n" ); document.write( "The trips there and back are equal distance, (1890 mi) write two distance equations
\n" ); document.write( "dist = time * speed
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\n" ); document.write( "3.375(s-w) = 1890
\n" ); document.write( "3.0(s + w) = 1890
\n" ); document.write( ":
\n" ); document.write( "It is convenient that we can simplify both these equations:
\n" ); document.write( "divide the 1st by 3.375
\n" ); document.write( "divide the 2nd by 3
\n" ); document.write( "resulting in two simple equations that can be used for elimination of w
\n" ); document.write( "s - w = 560
\n" ); document.write( "s + w = 630
\n" ); document.write( "----------------adding eliminates w, find s
\n" ); document.write( "2s = 1190
\n" ); document.write( "s = \"1190%2F2\"
\n" ); document.write( "s = 595 mph is the plane speed in still air
\n" ); document.write( "Find w
\n" ); document.write( "595 + w = 630
\n" ); document.write( "w = 630 - 595
\n" ); document.write( "w = 35 mph is the wind speed
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\n" ); document.write( "You can check these solutions using the 1st two equations with these values\r
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