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If we add 1 to the numerator and subtract 1 from the denominator of a given fraction, it becomes 1. It becomes 32тАЛ if 1 is added to the denominator of the given fraction while the numerator is left unchanged. The positive difference of numerator and denominator of the fraction is:
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2
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2
Set up linear equations from the two conditions and solve for numerator x and denominator y. Then find the positive difference тИгxтИТyтИг.
Let the given fraction be yxтАЛ. Adding 1 to the numerator and subtracting 1 from the denominator gives 1. Adding 1 to the denominator while leaving the numerator unchanged gives 32тАЛ.
yтИТ1x+1тАЛ=1andy+1xтАЛ=32тАЛ
Set up linear equations from the two conditions and solve for numerator x and denominator y. Then find the positive difference тИгxтИТyтИг.
Mixing up numerator and denominator modifications or calculating yтИТx instead of the positive difference тИгxтИТyтИг.
Step 1: Formulate the first equation
Let the fraction be yxтАЛ. Adding 1 to the numerator and subtracting 1 from the denominator gives 1: yтИТ1x+1тАЛ=1 This simplifies to x+1=yтИТ1, or yтИТx=2 (Equation 1).
yтИТx=2
Step 2: Formulate the second equation
If 1 is added to the denominator while the numerator remains unchanged, the fraction becomes 32тАЛ: y+1xтАЛ=32тАЛ Cross-multiplying gives 3x=2(y+1), which simplifies to 3xтИТ2y=2 (Equation 2).
3xтИТ2y=2
Step 3: Solve the system of equations
From Equation 1, y=x+2. Substitute this into Equation 2: 3xтИТ2(x+2)=2тЯ╣3xтИТ2xтИТ4=2тЯ╣x=6 Then find y: y=6+2=8
x=6,y=8
Step 4: Find the positive difference
The numerator is 6 and the denominator is 8. The positive difference between the numerator and denominator is: тИг6тИТ8тИг=2
тИг6тИТ8тИг=2
B is correct because solving the system of linear equations yields numerator x=6 and denominator y=8, giving a positive difference of тИг6тИТ8тИг=2.
Word problems involving fractions can always be translated into a system of two linear equations in two variables by setting up algebraic numerators and denominators.