Обчисли:
Розв'язок:
1) $\left(12\frac{3}{10} - 10\frac{1}{2}\right) \cdot \frac{5}{9} =$
$= \left(\frac{123}{10} - \frac{21}{2}\right) \cdot \frac{5}{9} =$
$= \frac{123 \cdot 5}{10 \cdot 9} - \frac{21 \cdot 5}{2 \cdot 9} =$
$= \frac{123}{18} - \frac{105}{18} = \frac{18}{18} = 1$;
2) $\frac{1}{36} : \left(1\frac{11}{12} - 1\frac{5}{9}\right) =$
$= \frac{1}{36} : \frac{33-20}{36} = \frac{1}{36} : \frac{13}{36} =$
$= \frac{1 \cdot 36}{36 \cdot 13} = \frac{1}{13}$.