1) x: 12 = 7:10; 10x = 12.7; x= 12.7- 10 x=

1) $$x:12 = 7:10$$

$$10 \cdot x = 12 \cdot 7$$

$$x = \frac{12 \cdot 7}{10} = \frac{84}{10} = 8,4$$

$$x = 8,4$$

Ответ: 8,4