Explicație pas cu pas:
6.
[tex] \frac{7}{2} = \frac{3 \times 2 + 1}{2} = 3 \frac{1}{2} \\ \frac{17}{6} = \frac{2 \times 6 + 5}{6} = 2 \frac{5}{6} \\ \frac{58}{9} = \frac{6 \times 9 + 4}{9} =6 \frac{4}{9} \\ \frac{111}{10} = \frac{11 \times 10 + 1}{10} = 11 \frac{1}{10} \\ \frac{87}{25} = \frac{3 \times 25 +12 }{25} = 3 \frac{12}{25} [/tex]
7.
[tex]5 \frac{1}{2} = \frac{5 \times 2 + 1}{2} = \frac{10 + 1}{2} = \frac{11}{2} \\ 3 \frac{3}{5} = \frac{3 \times 5 + 3}{5} = \frac{15 + 3}{5} = \frac{18}{5} \\ 6 \frac{5}{7} = \frac{6 \times 7 + 5}{7} = \frac{42 + 5}{7} = \frac{47}{7} \\ 11 \frac{10}{11} = \frac{11 \times 11 + 10}{11} = \frac{121 + 10}{11} \frac{131}{11} [/tex]
8.
[tex] \frac{1}{2} \times 12 = \frac{12}{2} = 6 \\ \frac{3}{5} \times 60 = \frac{3 \times 60}{5} = 3 \times 12 = 36 \\ \frac{4}{5} \times 75 = \frac{4 \times 75}{5} = 4 \times 15 = 60 \\ \frac{5}{2} \times 66 = \frac{5 \times 66}{2} = 5 \times 33 = 165 \\ \frac{5}{7} \times 21 = \frac{5 \times 21}{7} = 5 \times 3 = 15[/tex]
b.
[tex] \frac{10}{100} \times 100 = 10 \\ \frac{25}{100} \times 20 = \frac{1}{4} \times 20 = 5 \\ \frac{20}{100} \times 45 = \frac{1}{5} \times 45 = 9 \\ \frac{6}{100} \times 150 = 3 \times 3 = 9 \\ \frac{10}{100} \times \frac{2}{3} \times 300 = 10 \times 2 = 20[/tex]
9.
[tex] \frac{1}{4} + \frac{3}{4} + \frac{2}{4} = \frac{1 + 3 + 2}{4} = \frac{6}{4} = \frac{3}{2} = 1 \frac{1}{2} [/tex]
[tex] \frac{4}{6} + 1 \frac{1}{2} + 2 \frac{5}{3} = \frac{4}{6} + \frac{3}{2} + \frac{11}{3} = \frac{4 + 9 + 22}{3} = \frac{35}{6} = 5 \frac{5}{6} [/tex]
[tex] \frac{1}{4} + 2 \frac{1}{5} - \frac{7}{20} = \frac{1}{4} + \frac{11}{5} - \frac{7}{20} = \frac{5 + 44 - 7}{20} = \frac{42}{20} = \frac{21}{10} = 2 \frac{1}{10} [/tex]
[tex] \frac{1}{10} + \frac{3}{4} + 2 \frac{2}{15} - 1 \frac{1}{12} = \frac{1}{10} + \frac{3}{4} + \frac{32}{15} - \frac{13}{12} = \frac{6 + 45 + 128 - 65}{60} = \frac{114}{60} = \frac{19}{10} = 1 \frac{9}{10} [/tex]
