A committee appointed in pursuance of this Act may elect a chairman of its meetings, and if no chairman is elected, or if the chairman elected is not present at the time appointed for holding the same, the members present shall choose one of their number to be chairman of such meeting. A committee may meet or adjourn as it thinks proper. The quorum of a committee shall consist of such number of members as may be prescribed by the authority that appointed it, or, if no number be prescribed, of three members. Every question at a meeting of a committee shall be determined by a majority of votes of the members present and voting on that question, and in case of an equal division of votes the chairman shall have a second or casting vote.