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\[\textbf{а)}\ 20\ :\frac{4}{5} > 20\]
\[\textbf{б)}\ 4\frac{1}{2}\ :\frac{2}{3} > 4\frac{1}{2}\]
\[\textbf{в)}\frac{84}{121}\ :\frac{63}{110} > \frac{84}{121}\]
\[\textbf{г)}\ \ 32\ :9\frac{3}{5} < 32\]