CHECK: Brüche und Variablen (Addition)

1.) \( \frac{3}{2} + \frac{x}{2} = \frac{12}{2} \Rightarrow x = \)

2.) \( \frac{1}{4} + \frac{x}{4} = \frac{12}{8} \Rightarrow x = \)

3.) \( \frac{1}{7} + \frac{x}{21} = \frac{9}{21} \Rightarrow x = \)

4.) \( \frac{6}{40} + \frac{x}{20} = \frac{11}{5} \Rightarrow x = \)

5.) \( \frac{5}{14} + \frac{5}{x} = \frac{20}{7} \Rightarrow x = \)

6.) \( \frac{1}{3} + \frac{5}{x} = \frac{2}{5} \Rightarrow x = \)

7.) \( \frac{2}{7} + \frac{24}{x} = \frac{16}{14} \Rightarrow x = \)

8.) \( \frac{10}{6} + \frac{15}{x} = \frac{30}{12} \Rightarrow x = \)

9.) \( \frac{x}{24} + \frac{1}{24} = \frac{36}{48} \Rightarrow x = \)

10.) \( \frac{x}{5} + \frac{26}{10} = \frac{27}{5} \Rightarrow x = \)

11.) \( \frac{x}{78} + \frac{5}{39} = \frac{72}{156} \Rightarrow x = \)

12.) \( \frac{5}{20} + \frac{x}{40} = \frac{60}{160} \Rightarrow x = \)