document.write( "Question 201997: Respected sir,\r
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document.write( "plz help me to solve this arith problem...\r
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document.write( "1] Running at their respective constant rates, machine X takes 2 days longer to produce w widgets than machine Y. At these rates, if the two machines together produce 5/4 w widgets in 3 days, how many days would it take machine X alone to produce 2w widgets? \r
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document.write( "waiting for yurs reply sir.\r
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document.write( "Thank u.
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document.write( "Regards
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document.write( "Binita. \n" );
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Algebra.Com's Answer #152245 by ptaylor(2198)![]() ![]() You can put this solution on YOUR website! Let x=amount of days it takes Y to produce w widgets \n" ); document.write( "Then Y produces at the rate of w/x widgets per day \n" ); document.write( "x+2=amount of days it takes X to produce w widgets \n" ); document.write( "Then X produces at the rate of w/(x+2) widgets per day \n" ); document.write( "Together the two machines work at the rate of w/x + w/(x+2)=(w(x+2)+wx)/x(x+2) widgets per day \n" ); document.write( "But we are told that the two machines together work at the rate of (5/12)w widgets per day ((5/4)w widgets in 3 days =(5/12)w widgets per day))\r \n" ); document.write( "\n" ); document.write( "Now our first equation to solve is: \n" ); document.write( "(w(x+2)+wx)/x(x+2)=(5/12)w multiply each side by x(x+2) \n" ); document.write( "w(x+2)+wx=(5/12)wx(x+2) simplify \n" ); document.write( "wx+2w+wx=(5/12)wx^2+(10/12)wx \n" ); document.write( "2wx+2w=(5/12)wx^2+(10/12)wx multiply each term by 12 \n" ); document.write( "24wx+24w=5wx^2+10wx subtract 24wx and 24w from each side \n" ); document.write( "5wx^2-14wx-24w=0 Assuming w is not equal to zero, divide each term by w \n" ); document.write( "5x^2-14x-24=0 quadratic in standard form \n" ); document.write( "If we use the quadratic formula to solve, we get: \n" ); document.write( "x=(14+-26)/10 or \n" ); document.write( "x=40/10=4---number of days it takes Y to produce w widgets \n" ); document.write( "and \n" ); document.write( "x=-14/10----Disregard. Days in this problem are positive \n" ); document.write( "Now for X \n" ); document.write( "x+2=amount of days it takes X to produce w widgets or \n" ); document.write( "x+2=4+2=6----number of days it takes X to produce w widgets \n" ); document.write( "So X produces 2w widgets in 6*2=12 days--------------ans \n" ); document.write( "Another way to look at it: X produces at the rate of w/(x+2) widgets per day or \n" ); document.write( "w/(4+2)=w/6 widgets per day so in 12 days X produces (w/6)*12=2w widgets\r \n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |