A majority of the board of tax appeals shall constitute a quorum to transact business, and any vacancy does not impair the right of the remaining members to exercise all the powers of the board so long as a majority remains. Any investigation, inquiry, or hearing which the board is authorized to hold or undertake may be held or undertaken by or before any one member of the board.
All investigations, inquiries, hearings, and decisions of the board, and every order made by a member when approved and confirmed by the board and shown on its record of proceedings is deemed the order of the board.