II) 0.8+0.3-(-2/11)

Решение:

• \[ 0.8 + 0.3 - \left( -\frac{2}{11} \right) \]
• \[ 1.1 + \frac{2}{11} \]
• \[ \frac{11}{10} + \frac{2}{11} \]
• \[ \frac{11 \cdot 11 + 2 \cdot 10}{10 \cdot 11} = \frac{121 + 20}{110} = \frac{141}{110} \]

Ответ: 141/110