document.write( "Question 173693This question is from textbook Algebra Structure and Method Book 1
\n" ); document.write( ": I would appreciate your help on the following problem: The two digits in the numerator of a fraction whose value is 4/7 are reversed in its demoninator. The reciprocal of the fraction is the value obtained when 16 is added to the original numerator and 5 is subtracted from the original demonimator. Find the original fraction. I have 10t+u/10u+t=4/7; 10u+t/10t+u=10t+u+16/10u+t-5.
\n" ); document.write( "7(10t+u)=4(10u+t), 70t+7u=40u+4t, 66t=33u, t=3/6u. I'm not sure where to go from there. Thank you so much for any help you can give me. I appreciate it so much!
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Algebra.Com's Answer #128573 by gonzo(654)\"\" \"About 
You can put this solution on YOUR website!
i believe i stumbled into the answer.
\n" ); document.write( "your equation of 66t = 33u was good.
\n" ); document.write( "that means that u = 2t
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\n" ); document.write( "you should have made your second equation equal to 7/4
\n" ); document.write( "that would be:
\n" ); document.write( "(10t+u+16)/(10u+t-5) = 7/4
\n" ); document.write( "then you could have solved as follows:
\n" ); document.write( "cross multiply:
\n" ); document.write( "7*(10u+t-5) = 4*(10t+u+16)
\n" ); document.write( "working this through:
\n" ); document.write( "70u + 7t - 35 = 40t + 4u + 64
\n" ); document.write( "move things around to get the u and the t on the left side and the constants on the right side.
\n" ); document.write( "66u - 33t = 35 + 64
\n" ); document.write( "66u - 33t = 99
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\n" ); document.write( "substitute 2t for u to get
\n" ); document.write( "132t - 33t = 99
\n" ); document.write( "99t = 99
\n" ); document.write( "t = 1
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\n" ); document.write( "since u = 2t, your answers are:
\n" ); document.write( "t = 1
\n" ); document.write( "u = 2
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\n" ); document.write( "to prove:
\n" ); document.write( "12/21 = 4/7 if you divide numerator and denominator by 3
\n" ); document.write( "12 + 16 / 21 - 5 = 28/16 = 7/4 if you divide numerator and denominator by 4
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