2. Решите уравнения 1) 3/11 + x = 7/11; 2) x - 2/5 = 3/5; 3) 1/3 * x = 10/11

Решение:

• 1) \( \frac{3}{11} + x = \frac{7}{11} \)
  \( x = \frac{7}{11} - \frac{3}{11} \)
  \( x = \frac{7-3}{11} \)
  \( x = \frac{4}{11} \)
• 2) \( x - \frac{2}{5} = \frac{3}{5} \)
  \( x = \frac{3}{5} + \frac{2}{5} \)
  \( x = \frac{3+2}{5} \)
  \( x = \frac{5}{5} \)
  \( x = 1 \)
• 3) \( \frac{1}{3} x = \frac{10}{11} \)
  \( x = \frac{10}{11} : \frac{1}{3} \)
  \( x = \frac{10}{11} \cdot \frac{3}{1} \)
  \( x = \frac{10 \cdot 3}{11 \cdot 1} \)
  \( x = \frac{30}{11} \)

Ответ: 1) 4/11; 2) 1; 3) 30/11