Answer to Vote Ratio
JavaScript (ES6), 103 102 bytes
Needs to be run from the root level of api.stackexchange.com. Returns a Promise object containing the result.
n=&gt;fetch(`questions/${n}?site=codegolf`).then(r=&gt;r.json()).then(({items:[j]})=&gt;j.score/j.answer_count)


1 byte saved thanks to kamoroso94.

If requiring that it be run from a specific path is allowed then that becomes 92 90 bytes.
n=&gt;fetch(n+`?site=codegolf`).then(r=&gt;r.json()).then(({items:[j]})=&gt;j.score/j.answer_count)


Try it
Full URL added to enable it to work here.


f=
n=&gt;fetch(`//api.stackexchange.com/questions/${n}?site=codegolf`).then(r=&gt;r.json()).then(({items:[j]})=&gt;j.score/j.answer_count)
onchange=_=&gt;f(+i.value).then(t=&gt;o.innerText=t)
&lt;input id=i type=number&gt;&lt;pre id=o&gt;