Проверь себя. Тема «Умножение и деление рациональных чисел». 1. $-\frac{7}{8} \cdot 5\frac{1}{3}$.

1. $-\frac{7}{8} \cdot 5\frac{1}{3} = -\frac{7}{8} \cdot \frac{16}{3} = -\frac{7 \cdot 16}{8 \cdot 3} = -\frac{7 \cdot 2}{1 \cdot 3} = -\frac{14}{3} = -4\frac{2}{3}$ 2. $-0,006 : \left(-1\frac{2}{25}\right) = -\frac{6}{1000} : \left(-\frac{27}{25}\right) = \frac{6}{1000} \cdot \frac{25}{27} = \frac{6 \cdot 25}{1000 \cdot 27} = \frac{1 \cdot 1}{40 \cdot 9/2} = \frac{1 \cdot 1}{40 \cdot 4,5} = \frac{1}{40 \cdot 4,5} = \frac{1}{180} $ (Wait, let's recheck: $\frac{6}{1000} \cdot \frac{25}{27} = \frac{1}{1000} \cdot \frac{25}{4,5} = \frac{25}{4500} = \frac{1}{180}$. The answer provided in the textbook is $1/18$. Let's re-read the textbook, perhaps it is $1/180$. Ah, $-0.006$ is $6/1000$. $-1 \frac{2}{25} = -27/25$. $6/1000 \cdot 25/27 = (6/27) \cdot (25/1000) = (2/9) \cdot (1/40) = 2/360 = 1/180$. The book answer likely has a typo or I misread the decimal. Let's assume the task is as written). 3. $-\frac{3}{7} \cdot \left(-\frac{2}{3}\right) : \left(-4\frac{4}{9}\right) \cdot 2\frac{1}{3} = \left(\frac{3 \cdot 2}{7 \cdot 3}\right) : \left(-\frac{40}{9}\right) \cdot \frac{7}{3} = \frac{2}{7} \cdot \left(-\frac{9}{40}\right) \cdot \frac{7}{3} = -\left(\frac{2 \cdot 9 \cdot 7}{7 \cdot 40 \cdot 3}\right) = -\left(\frac{1 \cdot 3 cdot 1}{1 \cdot 20 cdot 1}\right) = -\frac{3}{20}$. (Wait, textbook says $-1 \frac{1}{2} = -3/2$. Let's recheck calculations: $-\frac{3}{7} \cdot (-\frac{2}{3}) = \frac{6}{21} = \frac{2}{7}$. This result divided by $-4\frac{4}{9} = -40/9$. So $2/7 : (-40/9) = 2/7 \cdot (-9/40) = -18/280 = -9/140$. Multiplied by $2\frac{1}{3} = 7/3$: $(-9/140) \cdot (7/3) = -(9 \cdot 7) / (140 \cdot 3) = -63/420 = -3/20$. The textbook answer is different. Let me re-calculate or check for transcription errors. Maybe it was multiplication instead of division? No, it looks like division. Given the textbook answers for 1 and 2, maybe there is a typo in the provided image text/source). 4. Из ряда чисел: $-9, -7, -5, 2, 4, 6$. Чтобы получить наименьший (самый отрицательный) результат, нужно перемножить положительное и отрицательное числа с наибольшими модулями. Это $-9$ и $6$. $-9 \cdot 6 = -54$.