[tex]\displaystyle 1)12\frac{5}{6}-6\frac{1}{4}-1\frac{1}{3}=(12-6-1)+(\frac{5}{6}-\frac{1}{4}-\frac{1}{3})=5+\frac{1}{4}=5\frac{1}{4}=\frac{21}{4}=5,25\\ \\2)3\frac{5}{6}+2\frac{7}{15}-1\frac{29}{30}=3+\frac{5}{6}+2+\frac{7}{15}-(1+\frac{29}{30})=(3+2-1)+(\frac{5}{6}+\frac{7}{15}-\frac{29}{30})=\\\\4+\frac{1}{3}=4\frac{1}{3}=\frac{13}{3}\\ \\3)4\frac{5}{14}+(5\frac{1}{12}-3\frac{4}{21})=\frac{61}{14}+\frac{53}{28}=\frac{25}{4}=6\frac{1}{4}=6,25[/tex]