[tex]6\dfrac{1}{8}=\dfrac{6\cdot8+1}{8}=\dfrac{48+1}{8}=\dfrac{49}{8}\\\\3\dfrac{5}{7}=\dfrac{3\cdot7+5}{7}=\dfrac{21+5}{7}=\dfrac{26}{7}\\------------------------------\\\\6\dfrac{1}{8}=6+\dfrac{1}{8}=\dfrac{6\cdot8}{8}+\dfrac{1}{8}=\dfrac{48}{8}+\dfrac{1}{8}=\dfrac{48+1}{8}=\dfrac{49}{8}\\\\3\dfrac{5}{7}=3+\dfrac{5}{7}=\dfrac{3\cdot7}{7}+\dfrac{5}{7}=\dfrac{21}{7}+\dfrac{5}{7}=\dfrac{21+5}{7}=\dfrac{26}{7}[/tex]
