Răspuns:
[tex] \frac{2}{11} + \frac{3}{11} + \frac{4}{11} + \frac{5}{11} + \frac{6}{11} + \frac{7}{11} = \\ \frac{5}{11} + \frac{4}{11} + \frac{5}{11} + \frac{6}{11} + \frac{7}{11} = \\ \frac{9}{11} + \frac{5}{11} + \frac{6}{11} + \frac{7}{11} = \\ \frac{14}{11} + \frac{6}{11} + \frac{7}{11} = \frac{20}{11} + \frac{7}{11} = \frac{27}{11} [/tex]
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