Răspuns:
[tex]a) \: \frac{1}{3} + \frac{1}{3} + \frac{1}{3} = \frac{1}{3} \times 3 = \frac{1}{3} \times \frac{3}{1} = \frac{1 \times 3}{3 \times 1} = \frac{3}{3} = 1[/tex]
[tex]b) \: \frac{7}{13} + \frac{7}{13} + \frac{7}{13} + \frac{7}{13} = \frac{7}{13} \times 4 = \frac{7}{13} \times \frac{4}{1} = \frac{7 \times 4}{13 \times 1} = \frac{28}{13} = 2 \frac{2}{13} [/tex]
[tex]c) \: \frac{3}{16} + \frac{3}{16} + ... + \frac{3}{16} = \frac{3}{16} \times 5 = \frac{3 \times 5}{16 \times 1} = \frac{15}{16} [/tex]
[tex]d) \: \frac{1}{5} + \frac{1}{5} + ... + \frac{1}{5} = \frac{1}{5} \times 10 = \frac{1 \times 10}{5 \times 1} = \frac{1 \times 2}{1 \times 1} = \frac{2}{1} = 2[/tex]
[tex]e) \: \frac{1}{10} + \frac{1}{10} + ... + \frac{1}{10} = \frac{1}{10} \times 50 = \frac{50}{10} = \frac{5}{1} = 5[/tex]
[tex] \frac{5}{23} + \frac{5}{23} + ... + \frac{5}{23} = \frac{5}{23} \times 100 = \frac{500}{23} = 21 \times \frac{17}{23} [/tex]
