Tìm x, biết? Tính giá trị của các biểu thức?

Để giải các bài toán trong hình, ta sẽ lần lượt giải từng bài một.

**Bài 9: Tìm x, biết:**
\[ x - \frac{5}{11} = \frac{1}{13} - \frac{1}{11} - \frac{1}{12} - \frac{1}{20} - \frac{1}{30} - \frac{1}{42} - \frac{1}{56} - \frac{1}{72} - \frac{1}{90} + \frac{1}{72} + \frac{1}{90} + \frac{1}{110} \]

Đầu tiên, ta tính giá trị của vế phải:
\[ \frac{1}{13} - \frac{1}{11} - \frac{1}{12} - \frac{1}{20} - \frac{1}{30} - \frac{1}{42} - \frac{1}{56} - \frac{1}{72} - \frac{1}{90} + \frac{1}{72} + \frac{1}{90} + \frac{1}{110} \]

Kết quả là:
\[ \frac{1}{13} - \frac{1}{11} - \frac{1}{12} - \frac{1}{20} - \frac{1}{30} - \frac{1}{42} - \frac{1}{56} + \frac{1}{110} \]

Sau khi tính toán, ta có:
\[ x - \frac{5}{11} = -0.202020202 \]

\[ x = -0.202020202 + \frac{5}{11} \]

\[ x = -0.202020202 + 0.454545454 \]

\[ x = 0.252525252 \]

**Bài 10: Tính giá trị của biểu thức:**
\[ A = \frac{1}{2} + \frac{1}{12} + \frac{1}{72} + \frac{3}{2022} \]

\[ A = \frac{1}{2} + \frac{1}{12} + \frac{1}{72} + \frac{3}{2022} \]

Sau khi tính toán, ta có:
\[ A = 0.5 + 0.083333333 + 0.013888889 + 0.001484403 \]

\[ A = 0.598706625 \]

**Bài 11: Tìm x, biết:**

a)
\[ \frac{1}{2} - \frac{3}{5} = -\left(\frac{1}{5}\right) - \frac{3}{20} \]

\[ \frac{1}{2} - \frac{3}{5} = -\frac{1}{5} - \frac{3}{20} \]

\[ \frac{1}{2} - \frac{3}{5} = -\frac{4}{20} - \frac{3}{20} \]

\[ \frac{1}{2} - \frac{3}{5} = -\frac{7}{20} \]

\[ x = -\frac{7}{20} \]

b)
\[ \frac{5}{9} x - \frac{1}{9} = \frac{11}{8} x \]

\[ \frac{5}{9} x - \frac{11}{8} x = \frac{1}{9} \]

\[ x \left(\frac{5}{9} - \frac{11}{8}\right) = \frac{1}{9} \]

\[ x \left(\frac{40}{72} - \frac{99}{72}\right) = \frac{1}{9} \]

\[ x \left(\frac{-59}{72}\right) = \frac{1}{9} \]

\[ x = \frac{1}{9} \times \frac{72}{-59} \]

\[ x = \frac{8}{-59} \]

c)
\[ 0.6x - \frac{1}{10} = \frac{1}{2} - \frac{1}{5} x \]

\[ 0.6x + \frac{1}{5} x = \frac{1}{2} + \frac{1}{10} \]

\[ 0.8x = \frac{6}{10} \]

\[ x = \frac{6}{10} \times \frac{10}{8} \]

\[ x = \frac{6}{8} \]

\[ x = \frac{3}{4} \]

d)
\[ \frac{1}{4} x - \frac{1}{3} x - \frac{1}{2} x = 0.2x - \frac{1}{8} \]

\[ \left(\frac{1}{4} - \frac{1}{3} - \frac{1}{2}\right) x = 0.2x - \frac{1}{8} \]

\[ \left(\frac{3}{12} - \frac{4}{12} - \frac{6}{12}\right) x = 0.2x - \frac{1}{8} \]

\[ \left(\frac{-7}{12}\right) x = 0.2x - \frac{1}{8} \]

\[ \left(\frac{-7}{12} - 0.2\right) x = -\frac{1}{8} \]

\[ \left(\frac{-7}{12} - \frac{2}{10}\right) x = -\frac{1}{8} \]

\[ \left(\frac{-35}{60} - \frac{12}{60}\right) x = -\frac{1}{8} \]

\[ \left(\frac{-47}{60}\right) x = -\frac{1}{8} \]

\[ x = \frac{-1}{8} \times \frac{60}{-47} \]

\[ x = \frac{60}{376} \]

\[ x = \frac{15}{94} \]

**Bài 12: Tính giá trị của các biểu thức sau:**

a)
\[ A = 0.25x - \frac{1}{6} x + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{5} x - 0.4\right) \text{ tại } x = \frac{1}{247} \]

\[ A = 0.25 \times \frac{1}{247} - \frac{1}{6} \times \frac{1}{247} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{5} \times \frac{1}{247} - 0.4\right) \]

\[ A = \frac{0.25}{247} - \frac{1}{6 \times 247} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{5 \times 247} - 0.4\right) \]

\[ A = \frac{0.25}{247} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4 - \frac{1}{1235} - 0.4\right) \]

\[ A = \frac{1}{988} - \frac{1}{1482} + \frac{1}{2} - \frac{1}{3} - \left(4