Răspuns :
[tex]9) \\ \\ a) \frac{2}{4} + \frac{5}{10} + \frac{3}{6} = \frac{1}{2} + \frac{1}{2} + \frac{1}{2} = \frac{1 + 1 + 1}{2} = \frac{3}{2} = 1 \frac{1}{2} \\ \\ b) \frac{4}{8} + \frac{9}{24} + \frac{15}{36} = \frac{1}{2} + \frac{3}{8} + \frac{5}{12} = \frac{1 \times 12}{2 \times 12} + \frac{3 \times 3}{8 \times 3} + \frac{5 \times 2}{12 \times 2} = \frac{12}{24} + \frac{9}{24} + \frac{10}{24} = \frac{12 + 9 + 10}{24} = \frac{31}{24} = 1 \frac{7}{24} \\ \\ c) \frac{7}{33} + \frac{16}{44} = \frac{7}{3} + \frac{4}{11} = \frac{7}{33} + \frac{4 \times 3}{11 \times 3} = \frac{7}{33} + \frac{12}{33} = \frac{7 + 12}{33} = \frac{19}{33} \\ \\ d) \frac{9}{30} + \frac{28}{20} + \frac{20}{40} = \frac{3}{10} + \frac{7}{5} + \frac{1}{2} = \frac{3}{10} + \frac{7 \times 2}{5 \times 2} + \frac{1 \times 5}{2 \times 5} = \frac{3}{10} + \frac{14}{10} + \frac{5}{10} = \frac{3 + 14 + 5}{10} = \frac{22}{10} = \frac{11}{5} = 2 \frac{1}{5} \\ \\ e) \frac{1}{3} + \frac{20}{30} + \frac{44}{33} + \frac{95}{57} = \frac{1}{3} + \frac{2}{3} + \frac{4}{3} + \frac{5}{3} = \frac{1 + 2 + 4 + 5}{3} = \frac{12}{3} = 4 \\ \\ f) \frac{231}{175} + \frac{231231}{175175} = \frac{33}{25} + \frac{33}{25} = \frac{33 + 33}{25} = \frac{66}{25} = 2 \frac{16}{25} \\ \\ 10) \\ \\ a) \frac{24}{25} + \frac{1}{4} + \frac{7}{100} = \frac{24 \times 4}{25 \times 4} + \frac{1 \times 25}{4 \times 25} + \frac{7}{100} = \frac{96}{100} + \frac{25}{100} + \frac{7}{100} = \frac{96 + 25 + 7}{100} = \frac{128}{100} = \frac{32}{25} = 1 \frac{7}{25} \\ \\ b) \frac{9}{20} + \frac{1}{180} + \frac{7}{60} + \frac{11}{30} = \frac{9 \times 9}{20 \times 9} + \frac{1}{180} + \frac{7 \times 3}{60 \times 3} + \frac{11 \times 6}{30 \times 6} = \frac{81}{180} + \frac{1}{180} + \frac{21}{180} + \frac{66}{180} = \frac{81 + 1 + 21 + 66}{180} = \frac{169}{180} \\ \\ c) \frac{11}{45} + \frac{13}{15} + \frac{1}{3} = \frac{11}{45} + \frac{13 \times 3}{15 \times 3} + \frac{1 \times 15}{3 \times 15} = \frac{11}{45} + \frac{39}{45} + \frac{15}{45} = \frac{11 + 39 + 15}{45} = \frac{65}{45} = \frac{13}{9} = 1 \frac{4}{9} \\ \\ d)5 + \frac{7}{20} + \frac{13}{20} = 5 + \frac{7 + 13}{20} = 5 + 1 = 6 \\ \\ e)( \frac{7}{24} + \frac{1}{8}) + ( \frac{7}{9} + \frac{13}{18}) = \frac{10}{24} + \frac{7}{9} + \frac{13}{18} = \frac{5}{12} + \frac{7}{9} + \frac{13}{18} = \frac{69}{36} = \frac{23}{12} \\ \\ f) \frac{3}{44} + \frac{9}{11} + \frac{3}{2} = \frac{3}{44} + \frac{9 \times 4}{11 \times 4} + \frac{3 \times 22}{2 \times 22} = \frac{3}{44} + \frac{36}{44} + \frac{66}{44} = \frac{3 + 36 + 66}{44} = \frac{105}{44} = 2 \frac{17}{44} [/tex]