Обчисли:
Розв'язок:
1) $4\frac{1}{3} \cdot \frac{3}{10} = \frac{13}{3} \cdot \frac{3}{10} = \frac{13}{10} = 1\frac{3}{10}$;
2) $\frac{7}{9} \cdot 1\frac{2}{7} = \frac{7}{9} \cdot \frac{9}{7} =$
$= \frac{7 \cdot 9}{9 \cdot 7} = 1$;
3) $\frac{4}{11} \cdot 4\frac{7}{12} = \frac{4}{11} \cdot \frac{55}{12} =$
$= \frac{4 \cdot 55}{11 \cdot 12} = \frac{5}{3} = 1\frac{2}{3}$;
4) $1\frac{1}{9} \cdot \frac{3}{10} = \frac{10}{9} \cdot \frac{3}{10} =$
$= \frac{10 \cdot 3}{9 \cdot 10} = \frac{1}{3}$;
5) $27 \cdot 1\frac{4}{9} = \frac{27}{1} \cdot \frac{13}{9} =$
$= \frac{27 \cdot 13}{1 \cdot 9} = 39$;
6) $4 \cdot 2\frac{5}{24} = \frac{4}{1} \cdot \frac{53}{24} =$
$= \frac{4 \cdot 53}{1 \cdot 24} = \frac{53}{6} = 8\frac{5}{6}$;
7) $1\frac{5}{6} \cdot 18 = \left(1 + \frac{5}{6}\right) \cdot 18 =$
$= 18 + \frac{5}{6} \cdot 18 = 18 + \frac{5 \cdot 18}{6 \cdot 1} =$
$= 18 + 15 = 33$;
8) $12 \cdot 3\frac{3}{8} = \frac{12}{1} \cdot \frac{27}{8} =$
$= \frac{12 \cdot 27}{1 \cdot 8} = \frac{81}{2} = 40\frac{1}{2}$.