# Question 2

Algebra Level 3

$\left\{ \begin{array}{l} \frac{{bcdef}}{a} = 4\\ \frac{{acdef}}{b} = 9\\ \frac{{abdef}}{c} = 16\\ \frac{{abcef}}{d} = \frac{1}{4}\\ \frac{{abcdf}}{e} = \frac{1}{9}\\ \frac{{abcde}}{f} = \frac{1}{{16}} \end{array} \right.$ Positive numbers $a,b,c,d,e,f$ satisfy the formulas above. Find the value of $(a+ c + e) - (b + d + f)$

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