482. Найдите значение выражения: a) \(\frac{3}{8} + \frac{1}{4} + \frac{5}{12}\) б) \(\frac{1}{2} + \frac{1}{3} - \frac{2}{5}\) в) \(\frac{5}{6} - \frac{3}{16} + \frac{5}{12}\) г) \(\frac{2}{3} - \frac{2}{5} + \frac{1}{4}\) д) \(\frac{7}{15} + \frac{2}{5} - \frac{2}{3}\) e) \(\frac{1}{4} + \frac{5}{6} - \frac{5}{12}\) ж) \((\frac{7}{20} + \frac{3}{10}) - (\frac{1}{8} + \frac{3}{16})\)

Решение: a) \(\frac{3}{8} + \frac{1}{4} + \frac{5}{12} = \frac{3 \cdot 3 + 1 \cdot 6 + 5 \cdot 2}{24} = \frac{9 + 6 + 10}{24} = \frac{25}{24}\) б) \(\frac{1}{2} + \frac{1}{3} - \frac{2}{5} = \frac{1 \cdot 15 + 1 \cdot 10 - 2 \cdot 6}{30} = \frac{15 + 10 - 12}{30} = \frac{13}{30}\) в) \(\frac{5}{6} - \frac{3}{16} + \frac{5}{12} = \frac{5 \cdot 8 - 3 \cdot 3 + 5 \cdot 4}{48} = \frac{40 - 9 + 20}{48} = \frac{51}{48} = \frac{17}{16}\) г) \(\frac{2}{3} - \frac{2}{5} + \frac{1}{4} = \frac{2 \cdot 20 - 2 \cdot 12 + 1 \cdot 15}{60} = \frac{40 - 24 + 15}{60} = \frac{31}{60}\) д) \(\frac{7}{15} + \frac{2}{5} - \frac{2}{3} = \frac{7 + 2 \cdot 3 - 2 \cdot 5}{15} = \frac{7 + 6 - 10}{15} = \frac{3}{15} = \frac{1}{5}\) e) \(\frac{1}{4} + \frac{5}{6} - \frac{5}{12} = \frac{1 \cdot 3 + 5 \cdot 2 - 5}{12} = \frac{3 + 10 - 5}{12} = \frac{8}{12} = \frac{2}{3}\) ж) \((\frac{7}{20} + \frac{3}{10}) - (\frac{1}{8} + \frac{3}{16}) = (\frac{7 + 3 \cdot 2}{20}) - (\frac{1 \cdot 2 + 3}{16}) = (\frac{7 + 6}{20}) - (\frac{2 + 3}{16}) = \frac{13}{20} - \frac{5}{16} = \frac{13 \cdot 4 - 5 \cdot 5}{80} = \frac{52 - 25}{80} = \frac{27}{80}\)