DALLAS — Alcoa swung to a third-quarter profit despite lower aluminum prices, as it was lifted by demand from automakers and by cost-cutting. The results beat expectations.

With the world awash in aluminum, Alcoa has been idling plants to cut smelting capacity. That helped the company cut its production costs by 9 percent, more than enough to offset a 7 percent drop in the cash price of the metal on the London market.

Alcoa said Tuesday that it earned $24 million, or 2 cents per share, in the July-September quarter, compared with a year-ago loss of $143 million, or 13 cents per share.

SEATTLE — The idea of a $15 minimum wage continues to build momentum in the Seattle area, with Mayor Mike McGinn saying he would support an effort to set the standard even higher. McGinn said he thought $15 was a “fair starting point” for the discussion. He cautioned that the issue was best handled legislatively and that the number would be determined by city council.The federal minimum wage is $7.25 an hour, and advocates have been pressing nationwide to push the number higher. In a small effort in the Seattle suburb of SeaTac, union-backed advocates were successful in getting a ballot measure that would raise the minimum wage to $15 per hour.