(5/6-3/8):3/4-(3/8+7/20):1 9/20 решите

$(\frac{5}{6}-\frac{3}{8}):\frac{3}{4}-(\frac{3}{8}+\frac{7}{20}):1\frac{9}{20}$ = $(\frac{20}{24}-\frac{9}{24}):\frac{3}{4}-(\frac{15}{40}+\frac{14}{40}):\frac{29}{20}$ = $\frac{11}{24}:\frac{3}{4}-\frac{29}{40}:\frac{29}{20}$ = $\frac{11}{24}*\frac{4}{3}-\frac{29}{40}*\frac{20}{29}$ = $\frac{11}{18}-\frac{1}{2}$ = $\frac{11}{18}-\frac{9}{18}$ = $\frac{2}{18}$ = $\frac{1}{9}$