SAN FRANCISCO — Marissa Mayer finally has something, however modest, to crow about.

Yahoo reported strong third-quarter financial performance on Tuesday, breaking a pattern of revenue declines and posting profits from its core operations that far exceeded Wall Street’s expectations.

And mobile, long a bête noire for the company, for the first time contributed meaningfully to its results. Ms. Mayer, Yahoo’s chief executive, told investors that mobile revenue exceeded $200 million in the quarter and she expected it to top $1.2 billion for the full year. Yahoo and its Tumblr unit together had 550 million monthly users on mobile devices during the quarter, up 17 percent from a year ago.

Ms. Mayer elaborated in an interview late Tuesday, saying that Yahoo was “outpacing industry growth” in the number of mobile users, the time people spend on its services and mobile ad revenue. “We needed our execution to improve, and it has improved,” she said.

But Ms. Mayer did not address the biggest concern on the minds of investors: How does Yahoo take advantage of its $43 billion in stock holdings in the Alibaba Group and Yahoo Japan?