Correct Answer: Option C

Explanation

\(\frac{3e + f}{3f - e}\) = \(\frac{2}{5}\)

= 3e + f

= 2 x 1

\(\frac{-e + 3f}{3e - f}\) = \(\frac{5 \times 3}{2}\)

= \(\frac{3e + 9f = 15}{10f = 17}\)

f = \(\frac{17}{10}\)

Sub. for equ. (1)

3e + \(\frac{17}{10}\) = 2

3e = 2 - \(\frac{17}{10}\)

\(\frac{3}{10}\)

e = \(\frac{3}{10}\) x \(\frac{1}{3}\)

= \(\frac{1}{10}\)

= e + 3f = \(\frac{1}{10}\) + \(\frac{3 \times}{10}\) = \(\frac{52}{10}\)

f - 3e = \(\frac{17}{10}\) - 3 x \(\frac{1}{10}\)

= \(\frac{14}{10}\)

= \(\frac{52}{10}\) x \(\frac{10}{14}\)

= \(\frac{26}{7}\)

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