№3. Выполните действия: а) \(12\frac{7}{20} + 7\frac{3}{20} - 4\) б) \(71\frac{8}{13} + 8\frac{12}{13} + \frac{9}{13}\) в) \(11\frac{21}{28} - 9\frac{12}{28} + \frac{1}{28}\) г) \(24 - 8\frac{7}{11} - 4\frac{9}{11}\) д) \((10 - 6\frac{15}{28}) + (2\frac{15}{28} - 1\frac{17}{28})\) е) \(5\frac{16}{24} - (2\frac{15}{24} - 1\frac{17}{24}) + 17\frac{5}{24}\)

Решение: а) \(12\frac{7}{20} + 7\frac{3}{20} - 4 = (12 + 7 - 4) + (\frac{7}{20} + \frac{3}{20}) = 15 + \frac{10}{20} = 15 + \frac{1}{2} = 15\frac{1}{2}\) Ответ: \(15\frac{1}{2}\) б) \(71\frac{8}{13} + 8\frac{12}{13} + \frac{9}{13} = (71 + 8) + (\frac{8}{13} + \frac{12}{13} + \frac{9}{13}) = 79 + \frac{8 + 12 + 9}{13} = 79 + \frac{29}{13} = 79 + 2\frac{3}{13} = 81\frac{3}{13}\) Ответ: \(81\frac{3}{13}\) в) \(11\frac{21}{28} - 9\frac{12}{28} + \frac{1}{28} = (11 - 9) + (\frac{21}{28} - \frac{12}{28} + \frac{1}{28}) = 2 + \frac{21 - 12 + 1}{28} = 2 + \frac{10}{28} = 2 + \frac{5}{14} = 2\frac{5}{14}\) Ответ: \(2\frac{5}{14}\) г) \(24 - 8\frac{7}{11} - 4\frac{9}{11} = 24 - (8\frac{7}{11} + 4\frac{9}{11}) = 24 - ((8 + 4) + (\frac{7}{11} + \frac{9}{11})) = 24 - (12 + \frac{16}{11}) = 24 - (12 + 1\frac{5}{11}) = 24 - 13\frac{5}{11} = 10\frac{6}{11}\) Ответ: \(10\frac{6}{11}\) д) \((10 - 6\frac{15}{28}) + (2\frac{15}{28} - 1\frac{17}{28}) = (3\frac{13}{28}) + (\frac{43}{28} - \frac{45}{28}) = 3\frac{13}{28} - \frac{2}{28} = 3\frac{11}{28}\) Ответ: \(3\frac{11}{28}\) е) \(5\frac{16}{24} - (2\frac{15}{24} - 1\frac{17}{24}) + 17\frac{5}{24} = 5\frac{16}{24} - (\frac{63}{24} - \frac{41}{24}) + 17\frac{5}{24} = 5\frac{16}{24} - \frac{22}{24} + 17\frac{5}{24} = 5\frac{16}{24} - \frac{22}{24} + 17\frac{5}{24} = (5 + 17) + (\frac{16}{24} - \frac{22}{24} + \frac{5}{24}) = 22 + \frac{16 - 22 + 5}{24} = 22 + \frac{-1}{24} = 21\frac{23}{24}\) Ответ: \(21\frac{23}{24}\)