Упр.306 Часть 2 ГДЗ Виленкин Жохов 6 класс (Математика)

Задача

1) -2,79 : 3,1 + 24,24 : 2,4;
2) 2,07 : (-2,3) + 13,13 : 1,3;
3) (1 — 1,5 * 1,4) * (-2,8);
4) (1 — 1,3 * 1,6) * (-3,2);
5) (1/3 — 5/6) : 3 1/2;
6) (-1/4 + 7/8) : (-1 1/4).

Подробный ответ

1) $$-2{,}79 : 3{,}1 + 24{,}24 : 2{,}4$$

$$-2{,}79 : 3{,}1 = -\frac{279}{310} = -0{,}9$$

$$24{,}24 : 2{,}4 = \frac{2424}{240} = 10{,}1$$

$$-0{,}9 + 10{,}1 = 9{,}2$$

2) $$2{,}07 : (-2{,}3) + 13{,}13 : 1{,}3$$

$$2{,}07 : (-2{,}3) = -\frac{207}{230} = -0{,}9$$

$$13{,}13 : 1{,}3 = \frac{1313}{130} = 10{,}1$$

$$-0{,}9 + 10{,}1 = 9{,}2$$

3) $$(1 — 1{,}5 \cdot 1{,}4)\cdot(-2{,}8)$$

$$1{,}5 \cdot 1{,}4 = \frac{3}{2}\cdot\frac{14}{10}=\frac{21}{10}$$

$$1-\frac{21}{10}=-\frac{11}{10}$$

$$-2{,}8=-\frac{14}{5}$$

$$-\frac{11}{10}\cdot\left(-\frac{14}{5}\right)=\frac{77}{25}=3{,}08$$

4) $$(1 — 1{,}3 \cdot 1{,}6)\cdot(-3{,}2)$$

$$1{,}3 \cdot 1{,}6=\frac{13}{10}\cdot\frac{16}{10}=\frac{52}{25}$$

$$1-\frac{52}{25}=-\frac{27}{25}$$

$$-3{,}2=-\frac{16}{5}$$

$$-\frac{27}{25}\cdot\left(-\frac{16}{5}\right)=\frac{432}{125}=3{,}456$$

5) $$\left(\frac{1}{3}-\frac{5}{6}\right):3\frac{1}{2}$$

$$\frac{1}{3}-\frac{5}{6}=\frac{2}{6}-\frac{5}{6}=-\frac{3}{6}=-\frac{1}{2}$$

$$3\frac{1}{2}=\frac{7}{2}$$

$$-\frac{1}{2}:\frac{7}{2}=-\frac{1}{2}\cdot\frac{2}{7}=-\frac{1}{7}$$

6) $$\left(-\frac{1}{4}+\frac{7}{8}\right):\left(-1\frac{1}{4}\right)$$

$$-\frac{1}{4}+\frac{7}{8}=-\frac{2}{8}+\frac{7}{8}=\frac{5}{8}$$

$$-1\frac{1}{4}=-\frac{5}{4}$$

$$\frac{5}{8}:\left(-\frac{5}{4}\right)=\frac{5}{8}\cdot\left(-\frac{4}{5}\right)=-\frac{1}{2}=-0{,}5$$