295. Эсептегиле: a) \frac{7}{8} + \frac{1}{8}; c) \frac{17}{23} - \frac{19}{23}; e) \frac{13}{24} - \frac{2}{13} + \frac{5}{12}; b) \frac{15}{28} - \frac{3}{28}; d) \frac{5}{21} - \frac{8}{21} - \frac{17}{21}; f) \frac{7}{9} \cdot \frac{2}{3} - \frac{5}{6} ✓

a)

1. \(\frac{7}{8} + \frac{1}{8} = \frac{7+1}{8} = \frac{8}{8} = 1\)
2. Ответ: 1

b)

1. \(\frac{15}{28} - \frac{3}{28} = \frac{15-3}{28} = \frac{12}{28} = \frac{3}{7}\)
2. Ответ: \(\frac{3}{7}\)

c)

1. \(\frac{17}{23} - \frac{19}{23} = \frac{17-19}{23} = \frac{-2}{23} = -\frac{2}{23}\)
2. Ответ: \(-\frac{2}{23}\)

d)

1. \(\frac{5}{21} - \frac{8}{21} - \frac{17}{21} = \frac{5-8-17}{21} = \frac{-20}{21} = -\frac{20}{21}\)
2. Ответ: \(-\frac{20}{21}\)

e)

1. \(\frac{13}{24} - \frac{2}{13} + \frac{5}{12} = \frac{13 \cdot 13}{24 \cdot 13} - \frac{2 \cdot 24}{13 \cdot 24} + \frac{5 \cdot 26}{12 \cdot 26} = \frac{169}{312} - \frac{48}{312} + \frac{130}{312} = \frac{169 - 48 + 130}{312} = \frac{251}{312}\)
2. Ответ: \(\frac{251}{312}\)

f)

1. \(\frac{7}{9} \cdot \frac{2}{3} - \frac{5}{6} = \frac{7 \cdot 2}{9 \cdot 3} - \frac{5}{6} = \frac{14}{27} - \frac{5}{6} = \frac{14 \cdot 2}{27 \cdot 2} - \frac{5 \cdot 9}{6 \cdot 9} = \frac{28}{54} - \frac{45}{54} = \frac{28-45}{54} = \frac{-17}{54} = -\frac{17}{54}\)
2. Ответ: \(-\frac{17}{54}\)