1 27 -- -- -- 5 20

$$ \frac{1}{5} - \frac{27}{20} = \frac{1 \cdot 4 - 27}{20} = \frac{4 - 27}{20} = \frac{-23}{20} = -1 \frac{3}{20} $$

Ответ: $$-1 \frac{3}{20}$$