Say back lawn = x, so front lawn \(= \frac{x}{3}\)

Total lawn \(= x + \frac{x}{3} = \frac{4x}{3}\) ................ (i)

back lawn mowed\(= \frac{2x}{3}\) & front lawn mowed \(= \frac{x}{6}\)

Total mowed \(= \frac{2x}{3} + \frac{x}{6} = \frac{5x}{6}\) .......... (ii)

Total Unmowed = (i) - (ii)

\(= \frac{4x}{3} - \frac{5x}{6} = \frac{x}{2}\) ................... (iii)

Unmowed Fraction = (iii) / (i)

\(\frac{x}{2} * \frac{3}{4x} = \frac{3}{8}\) (Answer = C)

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