When 8 is added to the numerator of a fraction and 12 is added to its denominator, the fraction becomes $$\frac{1}{2}$$. When 2 is subtracted from its numerator and denominator, the fraction becomes $$\frac{1}{8}$$. Find the original fraction.
Let's assume the original fraction is $$\frac{P}{Q}$$.
When 8 is added to the numerator of a fraction and 12 is added to its denominator, the fraction becomes $$\frac{1}{2}$$.
$$\frac{P+8}{Q+12} =Â \frac{1}{2}$$
2P+16 = Q+12
2P-QÂ = 12-16
2P-Q = -4Â Â Eq.(i)
When 2 is subtracted from its numerator and denominator, the fraction becomes $$\frac{1}{8}$$.
$$\frac{P-2}{Q-2} = \frac{1}{8}$$
8P-16 = Q-2
8P-Q = 16-2
8P-Q = 14Â Â Â Eq.(ii)
Eq.(ii)-Eq.(i) ==>Â 8P-Q-(2P-Q) = 14-(-4)
8P-Q-2P+Q = 14+4
6P = 18
P = 3
Put the value of 'P' in Eq.(i).
$$2\times3-Q = -4$$
6-Q = -4
Q = 6+4
Q = 10
Original fraction =Â $$\frac{P}{Q}\ =\ \frac{3}{10}$$
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