Verified Answer :

Lilith

\(\frac{20}{40}-\frac{21}{40}\cdot \frac{80}{7}=\frac{ ot20^1 }{ ot40^2} - \frac{ ot21^3}{ ot40^1} \cdot \frac{ ot80^2}{ ot7^1} = \frac{1}{2}- 6=-5\frac{1}{2}\)


\(\frac{20}{40} - \frac{21}{40} \cdot \frac{80}{7}= \frac{1}{2} - \frac{3\cdot7}{40}\cdot\frac{2\cdot40}{7}= \frac{1}{2} - \frac{3}{1}\cdot\frac{2}{1}= \frac{1}{2} -6=-5 \frac{1}{2}\)