Obliczenia
[tex]2\frac{1}{10}-\frac{3}{4}=2\frac{2}{20}-\frac{15}{20}=1\frac{22}{20}-\frac{15}{20}=1\frac{7}{20}\\\\1\frac{7}{18}-2\frac{2}{9}=1\frac{7}{18}-2\frac{4}{18}=-(2\frac{4}{18}-1\frac{7}{18})=-(1\frac{22}{18}-1\frac{7}{18})=-\frac{15}{18}=-\frac{5}{6}\\\\2\frac{1}{7}-5\frac{2}{3}=-(5\frac{2}{3}-2\frac{1}{7})=-(5\frac{14}{21}-2\frac{3}{21})=-3\frac{11}{21}[/tex]
