A rod of length $2\frac{2}{5} \mathrm{metre}$ is divided into five equal parts. Find the length of each equal parts.

If $A=3\frac{3}{8}$ and $B=6\frac{5}{8}$, find $A÷B$ and $B÷A$.

Simplify: $6+\left\{\frac{4}{3}+\left(\frac{3}{4}-\frac{1}{3}\right)\right\}$

Simplify: $8-\left\{\frac{3}{2}+\left(\frac{3}{5}-\frac{1}{2}\right)\right\}$

Simplify: $\frac{1}{4}\left(\frac{1}{4}+\frac{1}{3}\right)-\frac{2}{5}$

Simplify: $2\frac{3}{4}-\left[3\frac{1}{8}÷\left\{5-\left(4\frac{2}{3}-\frac{11}{12}\right)\right\}\right]$