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Form the pair of linear equations for th...

Form the pair of linear equations for the following problems and find their solution by substitution method.
A fraction becomes `(9)/(11)`, if 2 is added to both the numerator and the denominator. If, 3 is added to both the numerator and the denominator it becomes `(5)/(6)`. Find the fraction.

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To solve the problem, we need to form a pair of linear equations based on the given conditions and then solve them using the substitution method. Let's break down the steps: ### Step 1: Define Variables Let: - \( x \) = numerator of the fraction - \( y \) = denominator of the fraction ### Step 2: Form the First Equation According to the problem, if 2 is added to both the numerator and the denominator, the fraction becomes \( \frac{9}{11} \). This can be expressed as: \[ \frac{x + 2}{y + 2} = \frac{9}{11} \] Cross-multiplying gives: \[ 11(x + 2) = 9(y + 2) \] Expanding this: \[ 11x + 22 = 9y + 18 \] Rearranging the equation: \[ 11x - 9y + 4 = 0 \quad \text{(Equation 1)} \] ### Step 3: Form the Second Equation Next, if 3 is added to both the numerator and the denominator, the fraction becomes \( \frac{5}{6} \). This can be expressed as: \[ \frac{x + 3}{y + 3} = \frac{5}{6} \] Cross-multiplying gives: \[ 6(x + 3) = 5(y + 3) \] Expanding this: \[ 6x + 18 = 5y + 15 \] Rearranging the equation: \[ 6x - 5y + 3 = 0 \quad \text{(Equation 2)} \] ### Step 4: Solve the Equations Using Substitution Method From Equation 1: \[ 11x - 9y = -4 \quad \text{(1)} \] From Equation 2: \[ 6x - 5y = -3 \quad \text{(2)} \] We can express \( y \) in terms of \( x \) from Equation 1: \[ 9y = 11x + 4 \implies y = \frac{11x + 4}{9} \quad \text{(3)} \] ### Step 5: Substitute \( y \) in Equation 2 Substituting Equation (3) into Equation (2): \[ 6x - 5\left(\frac{11x + 4}{9}\right) = -3 \] Multiplying through by 9 to eliminate the fraction: \[ 54x - 5(11x + 4) = -27 \] Expanding: \[ 54x - 55x - 20 = -27 \] Combining like terms: \[ -x - 20 = -27 \] Adding 20 to both sides: \[ -x = -7 \implies x = 7 \] ### Step 6: Find \( y \) Substituting \( x = 7 \) back into Equation (3): \[ y = \frac{11(7) + 4}{9} = \frac{77 + 4}{9} = \frac{81}{9} = 9 \] ### Step 7: Conclusion The fraction is: \[ \frac{x}{y} = \frac{7}{9} \] ### Final Answer The required fraction is \( \frac{7}{9} \). ---
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