The shareholders present at a duly called or held meeting at which a quorum is present may continue to transact business until adjournment notwithstanding the withdrawal of enough shareholders to leave less than a quorum, if any action is approved by at least a majority of the shares required to constitute a quorum, in the absence of a quorum, any meeting of shareholders may be adjourned from time to time by the vote of a majority of the shares represented either in person or by proxy, but no other business may be transacted except as provided in the foregoing provisions of this section.