Shareholders in the Evening News Association yesterday approved the sale of the media company to Gannett Co. Inc. for $717 million. Gannett's acquisition of Detroit-based ENA, which publishes The Detroit News and four other daily newspapers and owns five television stations, including WDVM in Washington, D.C., will be complete by Feb. 15, said Mike Davis, ENA spokesman. Shareholders in the closely held company, many of them relatives of the company's founder, James E. Scripps, will receive $1,583 per share in the transaction.

Gannett, which publishes USA Today, in August offered to buy ENA while the media group was fighting a hostile tender offer by television producers Norman Lear and A. Jerrold Perenchio. Gannett, at ENA's invitation, topped the producers' offer by $151 million, and ENA directors voted to accept his bid.

When the transaction is complete, Gannett will publish 91 daily newspapers and own eight television stations and 15 radio stations, said Larry Fuller, Gannett director of communications.

Gannett has announced an agreement to sell the ENA's Detroit radio stations to a group of local businessmen for about $39 million, and plans to sell its two radio stations, WCZY AM and FM, before their licenses come up for renewal in 1989. The sales are necessary because of federal regulations on single ownership of newspaper and broadcast outlets in the same city.