Ronald,
Welcome! Feel free to ask any question you might have and offer advise if it can assist others.
Typically quorums are different for different things. A quorum for just a general meeting might be lower then the quorum needed to change the governing documents or to increase assessments. Some Associations even have the ability to have a reduced quorum at a second meeting if the first meeting didn't reach one. Quorum requirements can also be scattered throughout all of your Associations governing documents, so be sure to read all of them.
If your Association is incorporated, they will have to comply with
Missouri Corporate Law. This law does cover quorums but defers to the Associations governing documents:
Quorum requirement.
355.281. 1. Unless this chapter or the articles or bylaws provide for a higher or lower quorum, ten percent of the votes entitled to be cast on a matter must be represented at a meeting of members to constitute a quorum on that matter. It also includes an interesting point:
4. Unless one-third or more of the voting power is present in person or by proxy, the only matters that may be voted upon at an annual or regular meeting of members are those matters that are described in the meeting notice. This would only apply if you are a non-profit corporation. Check your governing documents to be sure.
As others have mentioned, quorums are achieved by members attending meetings or by receiving proxies from members unable to attend the meeting.
Tim