Today i met a 位 that's not a part of some compound word for the first time: 関取(位が十両以上)・・・, so i checked it's kunyomi, which turns out to be くらい. But i suspect that oftentimes it is read as い even as a separate noun. When do i read it as くらい and when as い?
Because a dictionary states, that it is also い when used as a:
1)
rank, place (e.g. first place).
2) decimal place.
3) counter for ghosts.
Now, after considering Mike's surprised question, and revising the list above, my conclusion is that save for place and counter for ghosts (which are still kind of compound words to me), 位 is read as くらい
Thank you for the comprehensive answer, Mike. And while we're at it, could you please elaborate on the decimal place part? Does it represent a specific digit after a decimal point? For example can i say 12.345(じゅうにてんさんよんご)の第三位(だいさんい)は5(ご)です about a figure 12.345 ?
小数点以下(第)何位 is more likely used for 四捨五入, 切り捨て or like that. When referring to a specific digit, 十分の一の位, 百分の一の位, etc. is more common, similar to 十の位 or 百の位.