document.write( "Question 825543: The numerator of a fraction is 1 more than the denominator. If 1 is added to the numerator, and the denominator is unchanged, the resulting fraction has a value of 3/4. Find the original fraction \n" ); document.write( "
Algebra.Com's Answer #497403 by jsmallt9(3758)\"\" \"About 
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Let n = the original numerator and d = the original denominator. Then the numerator with 1 added to it would be: n + 1.

\n" ); document.write( "With two variables we need two equations to solve this problem. \"The numerator of a fraction is 1 more than the denominator.\" translates into:
\n" ); document.write( "n = d + 1
\n" ); document.write( "and \"If 1 is added to the numerator, and the denominator is unchanged, the resulting fraction has a value of 3/4\" translates into:
\n" ); document.write( "\"%28n%2B1%29%2Fd+=+3%2F4\"

\n" ); document.write( "Now we can solve. Since the first equation is already solved for n, the Substitution Method seems like it would be easiest. Substituting for n in the second equation we get:
\n" ); document.write( "\"%28%28d%2B1%29%2B1%29%2Fd+=+3%2F4\"
\n" ); document.write( "Simplifying we get:
\n" ); document.write( "\"%28d%2B2%29%2Fd+=+3%2F4\"
\n" ); document.write( "Cross-multiplying we get:
\n" ); document.write( "\"%28d%2B2%29%2A4+=+d%2A3\"
\n" ); document.write( "which simplifies to:
\n" ); document.write( "\"4d%2B8+=+3d\"
\n" ); document.write( "Subtracting 4d we get:
\n" ); document.write( "\"8+=+-d\"
\n" ); document.write( "Multiplying (or dividing) both sides by -1 we get:
\n" ); document.write( "\"-8+=+d\"

\n" ); document.write( "Now we find the value for n. Using the first equation, n = d + 1, and the value we found for d, we should get n = -7. And since n and d are the original fraction:
\n" ); document.write( "\"%28-7%29%2F%28-8%29\"
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