\[b_{1} = 32;\ \ \ q = - \frac{1}{4};\ \ \]
\[S_{n} = \frac{b_{1}\left( 1 - q^{n} \right)}{1 - q}\]
\[S_{5} = \frac{32 \cdot \left( 1 - \left( - \frac{1}{4} \right)^{5} \right)}{1 - \left( - \frac{1}{4} \right)} =\]
\[= \frac{32 \cdot \left( 1 - \frac{1}{1024} \right)}{1 + \frac{1}{4}} =\]
\[= \frac{1023}{40} = 25\frac{23}{40}\]
\[Ответ:\ \ 25\frac{23}{40}.\]