\[\boxed{\mathbf{3.77}}\]
\[\frac{3}{4} = \frac{1}{4} + \frac{2}{4} = \frac{1}{4} + \frac{1}{2}\]
\[\frac{7}{12} = \frac{1}{12} + \frac{6}{12} = \frac{1}{12} + \frac{1}{2}\]
\[\frac{9}{20} = \frac{4}{20} + \frac{5}{20} = \frac{1}{5} + \frac{1}{4}\]
\[\frac{5}{8} = \frac{1}{8} + \frac{4}{8} = \frac{1}{8} + \frac{1}{2}\]
\[\frac{13}{36} = \frac{1}{36} + \frac{12}{36} = \frac{1}{36} + \frac{1}{3}\]