6 Найдите произведение: 2 a) 5 × 6 7 2 6) 9 × 11 5

6 Найдите произведение:

a) $$5\frac{2}{7} \times 6$$

$$5\frac{2}{7} = \frac{5 \times 7 + 2}{7} = \frac{35 + 2}{7} = \frac{37}{7}$$ $$\frac{37}{7} \times 6 = \frac{37 \times 6}{7} = \frac{222}{7} = 31\frac{5}{7}$$

Ответ: $$31\frac{5}{7}$$

б) $$9 \times 11\frac{2}{5}$$

$$11\frac{2}{5} = \frac{11 \times 5 + 2}{5} = \frac{55 + 2}{5} = \frac{57}{5}$$ $$9 \times \frac{57}{5} = \frac{9 \times 57}{5} = \frac{513}{5} = 102\frac{3}{5}$$

Ответ: $$102\frac{3}{5}$$