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Solve for n. \frac{3}{7 - n}= \frac{1}{n}

Question:

Solve for n.

{eq}\frac{3}{7 - n}= \frac{1}{n} {/eq}

Cross Multiplication:

Cross Multiplication is the technique that is used to solve the problem based on proportion. In this technique, each side of the equation is multiple by the denominators of the opposite side.

Answer and Explanation:


The expression is,

{eq}\frac{3}{{7 - n}} = \frac{1}{n} {/eq}


Solve the above expression with the help of cross multiplication.

{eq}\begin{align*} 3n &= 7 - n\\ 3n + n &= 7\\ 4n &= 7\\ n &= \frac{7}{4} \end{align*} {/eq}


Thus, the value for n is {eq}\dfrac{7}{4} {/eq}.


Learn more about this topic:

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