[tex]168|2\\.\ 84|2\\.\ 42|2\\.\ 21|3\\.\ \ 7|7\\.\ \ 1|\\\\56|2\\28|2\\14|2\\.\ 7|7\\.\ 1|[/tex]
[tex]168:56=\frac{2\cdot2\cdot2\cdot3\cdot7}{2\cdot2\cdot2\cdot7}\\\\=\frac{2\cdot2\cdot3\cdot7}{2\cdot2\cdot7}=\boxed{\frac{84}{28}}\\\\=\frac{2\cdot2\cdot2\cdot3}{2\cdot2\cdot2}=\boxed{\frac{24}{8}}\\\\=\frac{2\cdot3\cdot7}{2\cdot7}=\boxed{\frac{42}{14}}\\\\=\frac{2\cdot3}{2}=\boxed{\frac{6}{2}}\\\\=\boxed{\frac{3}{1}}\\\\=\frac{2\cdot2\cdot3}{2\cdot2}=\boxed{\frac{12}{4}}\\\\=\frac{3\cdot7}{7}=\boxed{\frac{21}{7}}[/tex]
