document.write( "Question 1072862: a fraction is such if both the denominator and the numerator are increased by 2/3,it becomes 17/20, if the numerator and the denominator are decreased by 1/2 then it becomes 9/11 find the original fraction.\r
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Algebra.Com's Answer #687725 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
Let's say the original fraction is \"x%2Fy\", where
\n" ); document.write( "\"x\"= numerator of the original fraction
\n" ); document.write( "\"y\"= denominator of the original fraction
\n" ); document.write( "The problem says that
\n" ); document.write( "\"%28x%2B2%2F3%29%2F%28y%2B2%2F3%29=17%2F20\" and \"%28x-1%2F2%29%2F%28y-1%2F2%29=9%2F11\"
\n" ); document.write( "Believe or not, that is a system of linear equations.
\n" ); document.write( "You can transform those equations into the equivalent equations
\n" ); document.write( "\"20x-17y=-2\" and \"11x-9y=1\"
\n" ); document.write( "and the solve the very ugly system.
\n" ); document.write( "That system has exactly one solution,
\n" ); document.write( "the one \"%22%28+x+%2C+y+%29%22\" pair that satisfies both equations.
\n" ); document.write( "If this were real life, you probably would have to solve the ugly system,
\n" ); document.write( "and find ugly solutions.
\n" ); document.write( "In math problems, you should expect to see signs of intelligent design,
\n" ); document.write( "or at least human design, so there has to be a nice answer.
\n" ); document.write( "You can also look the problem from another angle
\n" ); document.write( "\"%28x-1%2F2%29%2F%28y-1%2F2%29=9%2F11\"<-->\"%28y-1%2F2%29%2F%28x-1%2F2%29=11%2F9\"
\n" ); document.write( "is the equation of a line with slope \"11%2F9\"
\n" ); document.write( "that passes through point (1/2,1/2) and an infinite number of points (x,y).
\n" ); document.write( "With that slope, only a small fraction of those points will have positive integer coordinates.
\n" ); document.write( "\"%28y-1%2F2%29%2F%28x-1%2F2%29=11%2F9\"<-->\"%282y-1%29%2F%282x-1%29=11%2F9\"
\n" ); document.write( "has the obvious nice solution
\n" ); document.write( "\"system%282y-1=11%2C2x-1=9%29\"-->\"system%282y=12%2C2x=10%29\"-->\"system%28y=6%2Cx=5%29\" .
\n" ); document.write( "There are many other integer solutions,
\n" ); document.write( "but you would not expect them to make such a pretty pair.
\n" ); document.write( "Similarly,
\n" ); document.write( "\"%28x%2B2%2F3%29%2F%28y%2B2%2F3%29=17%2F20\"<-->\"%283x%2B2%29%2F%283y%2B2%29=17%2F20\"
\n" ); document.write( "has the obvious nice solution
\n" ); document.write( "\"system%283x%2B2=17%2C3y%2B2=20%29\"-->\"system%283x=15%2C3y=18%29\"-->\"system%28x=5%2Cy=6%29\" .
\n" ); document.write( "The original fraction is \"x%2Fy=highlight%285%2F6%29\" .
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