2 5/8+9/16+3 1/4

$$\left({\mathtt{2}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{5}}}{{\mathtt{8}}}}\right){\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{9}}}{{\mathtt{16}}}}{\mathtt{\,\small\textbf+\,}}\left({\mathtt{3}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{1}}}{{\mathtt{4}}}}\right)$$

$${\frac{{\mathtt{5}}}{{\mathtt{8}}}} = {\mathtt{0.625}}$$          $${\frac{{\mathtt{9}}}{{\mathtt{16}}}} = {\mathtt{0.562\: \!5}}$$        $${\frac{{\mathtt{1}}}{{\mathtt{4}}}} = {\mathtt{0.25}}$$

Start inside the brackets:

$$\left({\mathtt{2}}{\mathtt{\,\small\textbf+\,}}{\mathtt{0.625}}\right){\mathtt{\,\small\textbf+\,}}{\mathtt{0.562\: \!5}}{\mathtt{\,\small\textbf+\,}}\left({\mathtt{3}}{\mathtt{\,\small\textbf+\,}}{\mathtt{0.25}}\right)$$

$$\left({\mathtt{2.625}}\right){\mathtt{\,\small\textbf+\,}}{\mathtt{0.562\: \!5}}{\mathtt{\,\small\textbf+\,}}\left({\mathtt{3.25}}\right)$$

Then you just add the numbers:

$${\mathtt{2.625}}{\mathtt{\,\small\textbf+\,}}{\mathtt{0.562\: \!5}}{\mathtt{\,\small\textbf+\,}}{\mathtt{3.25}} = {\mathtt{6.437\: \!5}}$$