`\frac{1}{2}+\frac{1}{3}+\frac{1}{6}=\frac{3}{6}+\frac{2}{6}+\frac{1}{6}=\frac{3+2+1}{6}=\frac{6}{6}=1`
`\frac{5}{12}+\frac{5}{6}+\frac{3}{4}=\frac{5}{12}+\frac{10}{12}+\frac{9}{12}=\frac{5+10+9}{12}=\frac{24}{12}=2`
`1-(\frac{1}{5}+\frac{1}{2})=1-(\frac{2}{10}+\frac{5}{10})=1-\frac{7}{10}=\frac{10}{10}-\frac{7}{10}=\frac{3}{10}`