г) $$\frac{7}{8} -0,25+2,125 = \frac{7}{8} - \frac{1}{4} + 2\frac{1}{8} = \frac{7}{8} - \frac{2}{8} + \frac{17}{8} = \frac{5}{8} + \frac{17}{8} = \frac{22}{8} = \frac{11}{4} = 2\frac{3}{4} = 2,75$$
Ответ: $$2,75$$