Xerox Corp. continued to pay a price on Wall Street yesterday for its announcement late Friday that profits for the fourth quarter could be as much 40 percent below analyst expectations.

Just how big a price the company paid in the stock market, however, depends on how you view the new math of today's world of after-hours trading.

When the New York Stock Exchange closed Friday, Xerox was at $24.75, up $1. That was before Xerox President G. Richard Thoman delivered the bad news for the fourth quarter, blaming the company's misfortune on, among other things, slow sales because of year 2000 computer worries and problems in Brazil.

Almost immediately, the price of Xerox stock fell to a 52-week low of $19.87 1/2 in after-hours trading.

When the market opened yesterday Xerox shares began to move up once again, climbing as high as $22.43 3/4 before falling back to $21.12 1/2, up $1.25 for the day--but more than $3 a share below its Friday close.

"Whenever you see the stock go up it's a good day," said Xerox spokesman Jeffrey Simek.

In May, Xerox was selling for nearly $64 a share.

Some analysts attributed yesterday's rise in the Xerox price to bargain hunters. But analysts appeared convinced that the problems facing Xerox were at best a company problem or at worst a problem confined to the office equipment business and not some new economic virus that would have an impact on the whole technology sector.

Shares of office equipment companies such as Pitney Bowes Inc., Lexmark International Group Inc. and Ikon Office Solutions Inc. were all off yesterday although not by much.

In his announcement last Friday, Thoman cited four factors behind his new earnings estimate. He said high-end printing and publishing equipment sales were "significantly constrained because of a focus on Y2K mitigation efforts and customer network lockdowns, which appear to be intensifying in December." The Y2K bug refers to the possibility that some computers may not be able to properly read dates when the calendar turns from 1999 to 2000.

Another factor was the higher than expected cost of the company's own customer administration reorganization plan and its impact on sales productivity.

Thoman also attributed the lower earnings outlook to difficulties overseas. He said profit from the company's Brazilian operation would be substantially below expectations because of the continuing economic weakness from that country's currency devaluation earlier this year. In Europe, the problem was the adverse impact of the stronger U.S. dollar against European currencies, resulting in lower revenue and profit.

With the exception of the European currency situation, the company predicted improvement in all the other problems next year.

"While I am disappointed with these adverse developments the primary reasons are clearly unrelated to long-term fundamentals," Thoman said. "In 2000, the Y2K issue disappears, the U.S. customer administration issues will progressively improve, we expect some recovery in Brazil and our sales force reorganization will have been implemented."

Simek said yesterday that the company expected next year to be two contrasting halves. He predicted some of the issues of the fourth quarter would continue into the beginning of 2000, while business would be back on track in the second half.

CAPTION: Xerox CEO G. Richard Thoman delivered profit news on Friday.