\[\boxed{\mathbf{813}.}\]
\[1)\ \frac{\log_{5}2}{\log_{5}6} + \frac{\log_{4}3}{\log_{4}6} = \log_{6}2 +\]
\[+ \log_{6}3 = \log_{6}(2 \cdot 3) =\]
\[= \log_{6}6 = 1.\]
\[2)\ \left( \log_{7}{2 + \frac{1}{\log_{5}7}} \right) \cdot lg7 =\]
\[= \left( \log_{7}2 + \log_{7}5 \right) \cdot \frac{1}{\log_{7}10} =\]
\[= \frac{\log_{7}(2 \cdot 5)}{\log_{7}10} =\]
\[= \frac{\log_{7}10}{\log_{7}10} = 1.\]
\[3)\ \frac{2\log_{2}3}{\log_{4}9} = \frac{2\log_{2}3}{\log_{4}3^{2}} =\]
\[= \frac{2\log_{2}3}{\log_{2}3} = 2.\]