Вычислите: 3/5:5/6+2 1/2*2/5-1:1 1/9.

\[\frac{3}{5}\ :\ \frac{5}{6} + 2\frac{1}{2}\ \bullet \ \frac{2}{5} - 1\ :1\frac{1}{9} =\]

\[= \frac{3 \bullet 6}{5 \bullet 5} + \frac{5 \bullet 2}{2 \bullet 5} - \frac{1 \bullet 9}{1 \bullet 10} =\]

\[= \frac{18^{\backslash 2}}{25} + 1 - \frac{9^{\backslash 5}}{10} =\]

\[= 1 + \frac{36 - 45}{50} = 1 - \frac{9}{50} =\]

\[= 1 - \frac{18}{100} = 1 - 0,18 = 0,82.\]