SOLUTION: In a certain fraction, the denominator is 4 larger than the numerator. If 2 is added to both the numerator and the denominato, the result is 3/5. Find the original fraction. Tha

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Question 1046192: In a certain fraction, the denominator is 4 larger than the numerator. If 2 is added to both the numerator and the denominato, the result is 3/5. Find the original fraction.
Thanks for your reply Sir/Ma'am!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let the fraction be +a%2Fb+
(1) +b+=+a+%2B+4+
(2) +%28+a+%2B+2+%29+%2F+%28+b+%2B+2+%29+=+3%2F5+
-------------------------------
Plug (1) into (2)
(2) +%28+a+%2B+2+%29+%2F+%28+a+%2B+4+%2B+2+%29+=+3%2F5+
(2) +%28+a+%2B+2+%29+%2F+%28+a+%2B+6+%29+=+3%2F5+
Multiply both sides by +5%2A%28+a+%2B+6+%29+
(2) +5%2A%28+a+%2B+2+%29+=+3%2A%28+a+%2B+6+%29+
(2) +5a+%2B+10+=+3a+%2B+18+
(2) +2a+=+8+
(2) +a+=+4+
and
(1) +b+=+a+%2B+4+
(1) +b+=+4+%2B+4+
(1) +b+=+8+
--------------------
The original fraction is +4%2F8+
check:
(2) +%28+a+%2B+2+%29+%2F+%28+b+%2B+2+%29+=+3%2F5+
(2) +%28+4+%2B+2+%29+%2F+%28+8+%2B+2+%29+=+3%2F5+
(2) +6%2F10+=+3%2F5+
(2) +3%2F5+=+3%2F5+
OK