6 feet 8 inches = 6 + \( \frac{8}{12}\) = \(\frac{20}{3}\) feet
\( \frac{15}{x+25}\) = \( \frac{\frac{20}{3}}{25}\)
\(15(75) = 20 (x+25)\)
\( 1125 = 20x +500 \)
\(x = \frac{1125-500}{20}\)
\(x = 31.25\)