296. Эсептегиле: a) \frac{7}{15} - \frac{13}{15}; c) -\frac{1}{38} - \frac{29}{38}; e) \frac{3}{13} + \frac{57}{26} \cdot \frac{4}{19}; b) \frac{5}{7} + \frac{9}{7}; d) \frac{13}{27} + \frac{15}{27} - \frac{7}{27} - \frac{17}{27}; f) \frac{7}{19} \cdot 5 - \frac{4}{5} : \frac{76}{85}.

a)

1. \(\frac{7}{15} - \frac{13}{15} = \frac{7-13}{15} = \frac{-6}{15} = -\frac{2}{5}\)
2. Ответ: \(-\frac{2}{5}\)

b)

1. \(\frac{5}{7} + \frac{9}{7} = \frac{5+9}{7} = \frac{14}{7} = 2\)
2. Ответ: 2

c)

1. \(-\frac{1}{38} - \frac{29}{38} = \frac{-1-29}{38} = \frac{-30}{38} = -\frac{15}{19}\)
2. Ответ: \(-\frac{15}{19}\)

d)

1. \(\frac{13}{27} + \frac{15}{27} - \frac{7}{27} - \frac{17}{27} = \frac{13+15-7-17}{27} = \frac{4}{27}\)
2. Ответ: \(\frac{4}{27}\)

e)

1. \(\frac{3}{13} + \frac{57}{26} \cdot \frac{4}{19} = \frac{3}{13} + \frac{57 \cdot 4}{26 \cdot 19} = \frac{3}{13} + \frac{3 \cdot 2}{13 \cdot 1} = \frac{3}{13} + \frac{6}{13} = \frac{3+6}{13} = \frac{9}{13}\)
2. Ответ: \(\frac{9}{13}\)

f)

1. \(\frac{7}{19} \cdot 5 - \frac{4}{5} : \frac{76}{85} = \frac{7}{19} \cdot \frac{5}{1} - \frac{4}{5} \cdot \frac{85}{76} = \frac{7 \cdot 5}{19 \cdot 1} - \frac{4 \cdot 17}{1 \cdot 76} = \frac{35}{19} - \frac{17}{19} = \frac{35-17}{19} = \frac{18}{19}\)
2. Ответ: \(\frac{18}{19}\)