Denominator 80875

Given a fraction whose denominator is 2 greater than its numerator. If we increase both the numerator and the denominator of this fraction by 7, we get the fraction 5/6. Which fraction is it?

Correct answer:

x =  3/5

Step-by-step explanation:

$$\begin{gathered} x=\frac{a}{a+2} \\ \frac{a+7}{a+2+7}=\frac{5}{6} \\ 6(a+7)=5\cdot (a+9) \\ 6\cdot (a+7)=5\cdot (a+9) \\ a=3 \\ a=\frac{3}{1}=3 \\ a=3 \\ x=\frac{a}{a+2}=\frac{3}{3+2}=\frac{3}{5}=0.6 \end{gathered}$$

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