Ответ:

а)

\(2\frac{5}{6}+3\frac{3}{4}-4\frac{1}{2}=\frac{35}{6}+\frac{15}{4}-\frac{9}{2}=\frac{61}{12}\).

\(\frac{61}{12}\cdot0,6+2,75=\frac{61}{12}\cdot\frac{3}{5}+\frac{11}{4}=\frac{61}{20}+\frac{55}{20}=\frac{116}{20}=5,8\).

б)

\(11,825:2,2=5,375\).

\((1\frac{1}{3}+1\frac{1}{6})\cdot1,35=(\frac{4}{3}+\frac{7}{6})\cdot\frac{27}{20}=\frac{5}{2}\cdot\frac{27}{20}=3,375\).

\(5,375-3,375=2\).

Ответ: а) 5,8; б) 2.