ж) -5\frac{3}{28} + 4\frac{5}{12};

ж) -5\frac{3}{28} + 4\frac{5}{12} = -\frac{5 * 28 + 3}{28} + \frac{4 * 12 + 5}{12} = -\frac{143}{28} + \frac{53}{12} = -\frac{143 * 3}{28 * 3} + \frac{53 * 7}{12 * 7} = -\frac{429}{84} + \frac{371}{84} = \frac{-429 + 371}{84} = \frac{-58}{84} = -\frac{29}{42}