First off:
$${\frac{{\mathtt{45}}}{{\mathtt{360}}}} = {\frac{{\mathtt{1}}}{{\mathtt{8}}}}$$
$${\frac{{\mathtt{1}}}{{\mathtt{8}}}}{\mathtt{\,\times\,}}\left({\mathtt{2}}\right) = {\frac{{\mathtt{1}}}{{\mathtt{4}}}}$$
And then it gets a bit harder from there.
$${\frac{{\mathtt{1}}}{{\mathtt{4}}}}{\mathtt{\,\times\,}}{\mathtt{75}} = {\frac{{\mathtt{1}}}{{\mathtt{4}}}}{\mathtt{\,\times\,}}\left({\frac{{\mathtt{75}}}{{\mathtt{1}}}}\right)$$
$${\frac{{\mathtt{1}}}{{\mathtt{4}}}}{\mathtt{\,\times\,}}\left({\frac{{\mathtt{75}}}{{\mathtt{1}}}}\right) = {\frac{{\mathtt{75}}}{{\mathtt{4}}}}$$
So, in terms of pi, the answer can be one of the two below (depending on if asked to keep in fraction form or not)
$$\left({\frac{{\mathtt{75}}}{{\mathtt{4}}}}\right){\mathtt{\,\times\,}}{\mathtt{\pi}}$$
OR
$${\mathtt{18.75}}{\mathtt{\,\times\,}}{\mathtt{\pi}}$$
If it aska you to leave it in terms of pi, then one of the two above is your answer. However, if it is asking for a number (no pi) then go on.
18.75pi = 58.9048622548086232
Rounding, that gives 58.9, which is your final answer.