a=\frac{2\frac{2}{3}}{2\frac{4}{5}+3,7*\frac{20}{37}:\frac{5}{6}}-\frac{2}{3}*\frac{4}{5}:(1,1-0,3)=
=\frac{\frac{8}{3}}{2,8+\frac{\not37^1}{\not10^1}*\frac{\not20^2}{\not37^1}*\frac{6}{5}}-\frac{8}{15}:0,8=
=\frac{\frac{8}{3}}{2,8+\frac{12}{5}}-\frac{8}{15}:\frac{8}{10}=
=\frac{\frac{8}{3}}{2,8+2,4}-\frac{\not8^1}{\not15^3}*\frac{\not10^2}{\not8^1}=
=\frac{\frac{8}{3}}{5,2}-\frac{2}{3}=
=\frac{\frac{8}{3}}{\frac{52}{10}}-\frac{2}{3}=
=\frac{\not8^2}{3}*\frac{10}{\not52^{13}}-\frac{2}{3}=
=\frac{2}{3}(\frac{10}{13}-1)=
=\frac{2}{3}(\frac{10}{13}-\frac{13}{13})=
=\frac{2}{\not3^1}*(-\frac{\not3^1}{13})=
=-\frac{2}{13}
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a=-\frac{2}{13}
156\%*a=\frac{\not156^{12}}{100}*(-\frac{2}{\not13^1})=\frac{12}{100}*(-2)=-\frac{24}{100}=-0,24