Mo. Rev. Stat. § 355.276: Number of votes per member.

1. Unless the articles or bylaws provide otherwise, each member is entitled to one vote on each matter voted on by the members.

2. Unless the articles or bylaws provide otherwise, if a membership stands of record in the names of two or more persons their acts with respect to voting shall have the following effect:

(1) If only one votes, such act binds all; and

(2) If more than one votes, the vote shall be divided on a pro rata basis.