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the denominator of a fraction is 3 more than the numerator. if both the numerator and denominator are increased by 4, the new fraction is equal to 3/4. what is the original fraction

User IPO
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1 Answer

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Explanations:

Let the numerator of the fraction be x and let the denominator be y.

Hence, the original fraction is:


(x)/(y)

It is given that the denominator is 3 more than the numerator. It follows that:


y=x+3

It is also given that when both the numerator and denominator are increased by 4, the new fraction is equal to 3/4. This implies mathematically to the equation:


(x+4)/(y+4)=(3)/(4)

Simplify this equation:


\begin{gathered} 4(x+4)=3(y+4) \\ \Rightarrow4x+16=3y+12 \end{gathered}

Substitute y=x+3 into this equation:


4x+16=3(x+3)+12

Solve the equation for x:


\begin{gathered} \Rightarrow4x+16=3x+9+12 \\ Collect\text{ like terms:} \\ \Rightarrow4x-3x=9+12-16 \\ \Rightarrow x=5 \end{gathered}

Substitute x=5 into the equation y=x+3:


y=5+3=8

Hence, x=5, and y=8.

It follows that the original fraction is 5/8.

Answer:

The original fraction is 5/8.

User Sproketboy
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