document.write( "Question 161535: togo flew his ultralight plane to a landing field 30 mi away. With the wind, the flight took 3/5h. Returning against the wind, the flight took 5/6h. Find the rate of the plane in still air and the rate of the wind. \n" ); document.write( "
Algebra.Com's Answer #119007 by gonzo(654)\"\" \"About 
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togo flies 30 miles in 3/5 of an hour with the wind.
\n" ); document.write( "togo flies 30 miles in 5/6 of an hour against the wind.
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\n" ); document.write( "his rate of speed with the wind was 30 / (3/5) = 30*5/3 = 150/3 = 50 mph.
\n" ); document.write( "his rate of speed against the wind was 30 / (5/6) = 30*6/5 = 6*6 = 36 mph.
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\n" ); document.write( "3/5 of an hour times 50 mph = 30 miles.
\n" ); document.write( "5/6 of an hour times 36 mph = 30 miles.
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\n" ); document.write( "mph looks good.
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\n" ); document.write( "going he was with the wind.
\n" ); document.write( "his rate of speed then was the airplane speed plus the wind speed.
\n" ); document.write( "coming back he was against the wind.
\n" ); document.write( "his rate of speed then was the airplane speed minus the wind speed.
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\n" ); document.write( "50 mph = A + W
\n" ); document.write( "36 mph = A - W
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\n" ); document.write( "looks like A + W - (A - W) should equal 50 - 36.
\n" ); document.write( "removing parentheses, equation becomes
\n" ); document.write( "A + W - A + W = 14.
\n" ); document.write( "combining like terms, the equation becomes
\n" ); document.write( "2*W = 14.
\n" ); document.write( "dividing both sides by 2, equation becomes
\n" ); document.write( "W = 7.
\n" ); document.write( "if W = 7, then A can be found as follows:
\n" ); document.write( "50 = A + 7
\n" ); document.write( "A = 43.
\n" ); document.write( "likewise,
\n" ); document.write( "36 = A - 7
\n" ); document.write( "A = 43.
\n" ); document.write( "since the airplane speed is the same, it looks like the answer is good.
\n" ); document.write( "solving in the original equations, we get
\n" ); document.write( "3/5 * (43 + 7) = 30
\n" ); document.write( "3/5 * 50- = 30
\n" ); document.write( "30 = 30
\n" ); document.write( "good.
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\n" ); document.write( "5/6 * (43 - 7) = 30
\n" ); document.write( "5/6 * 36 = 30
\n" ); document.write( "30 = 30
\n" ); document.write( "good.
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\n" ); document.write( "answer is W = 7 and A = 43.
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