Computer Sciences Corp. has agreed to buy Long Beach-based health care consulting and information technology company First Consulting Group Inc. for $365 million.

Computer Sciences, based in El Segundo, said it will buy First Consulting for $13 per share, a 30 percent premium on the company’s Tuesday’s closing price of $9.98.

The boards of directors of both companies have approved the agreement and expect the deal to close during the first quarter of 2008. First Consulting shareholders, however, must first approve the takeover.

The deal comes after First Consulting exited the software products business in September by selling its FirstGateways business to Mason, Ohio-based MedPlus Inc. for $8 million.

Shares in Computer Sciences rose 34 cents to $57.69, while shares in First Consulting soared 27 percent, or $2.72, to $12.70.