Решебник по математике 5 класс Виленкин Часть 1, 2 Часть 2. Параграф 5. Обыкновенные дроби Задание 227

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\[\textbf{а)}\ \frac{6}{19} - \frac{3}{19} + \frac{15}{19} = \frac{6 - 3 + 15}{19} =\]

\[= \frac{3 + 15}{19} = \frac{18}{19}\ \]

\[\textbf{б)}\ \frac{19}{21} - \frac{17}{21} + \frac{9}{21} =\]

\[= \frac{19 - 17 + 9}{21} = \frac{2 + 9}{21} = \frac{11}{21}\]

\[\textbf{в)}\ \frac{25}{32} - \frac{6}{32} + \frac{19}{32} =\]

\[= \frac{25 - 6 + 19}{32} = \frac{19 + 19}{32} = \frac{38}{32}\ \]

\[\textbf{г)}\ \left( \frac{19}{23} - \frac{8}{23} \right) + \left( \frac{16}{23} - \frac{11}{23} \right) =\]

\[= \frac{19 - 8}{23} + \frac{16 - 11}{23} = \frac{11}{23} + \frac{5}{23} =\]

\[= \frac{11 + 5}{23} = \frac{16}{23}\ \]