If a fraction is reduced to its simplest form, the numerator is less than the denominator by 3. When both the numerator and denominator are increased by 2, the fraction is increased by 1/20.
Find the original fraction.
F.4 MATHS ... help,,,,
2007-03-05 5:34 am
回答 (1)
2007-03-05 5:45 am
✔ 最佳答案
Let the original fraction be (y-3)/y[(y-3)+2]/(y+2)-(y-3)/y=1/20
(y-1)/(y+2)-(y-3)/y=1/20
[y(y-1)-(y+2)(y-3)]/y(y+2)=1/20
[(y²-y)-(y²-y-6)]/y(y+2)=1/20
6/y(y+2)=1/20
y(y+2)/20=6
y²+2y-120=0
(y-10)(y+12)=0
y=10 or y=-12 (rejected)
Therefore y=10.
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