The Securities and Exchange Commission voted 3-1 to hold public hearings in December on the New York Stock Exchange's proposal to abandon its one share, one vote rule. The NYSE now prohibits listed companies from having different classes of stock with unequal voting rights . . . Great Western Savings & Loan has agreed to buy four branches of Miami-based Centrust Savings Bank in Florida. Terms were not disclosed . . . Money-market fund assets fell $1.8 billion in the week ended Wednesday to $237.38 billion, the Investment Company Institute said.