Solution
To find the best expression, we need to first approximate the values before dividing it
[tex]\begin{gathered} 6\frac{3}{4}=6.75 \\ \\ We\text{ approximate to get} \\ 6.75\cong7 \end{gathered}[/tex]Similarly
[tex]\begin{gathered} 1\frac{2}{3}=1.6666666666667 \\ \\ we\text{ approximate to get} \\ \\ 1.6666667\cong2 \end{gathered}[/tex]Therefore, the answer is
[tex]7\div2[/tex]