Levi Strauss & Co. said yesterday its profits for the first quarter increased 25 percent to $32.7 million ($1.48 a share) from $26.2 million ($1.17) a year ago. Sales climbed 20 percent to $371.3 million from $310.6 million.

The company said a tendence by retailers to make purchases closer to their desired shipping date, coupled with bad weather in most parts of the country, reduced the company's unshipped orders positions.

General Dynamics Corp. of St. Louis reported yesterday a 3.8 percent increase in full-year profits to $103.4 million ($9.51 a share)compared period a year ago. Sales rose 13.7 percent the fourth quarter, the company said earnings rose 1.7 perscent to $29.2 million ($2.73 a share) from $28.7 million ($2.62) while sales increased 3.5 percent to $750.6 million from $724.7 million.

General Dynamics said it is extending its stop work deadline on the attack submarine program for two months to allow additional time for negotiation with the U.S. Navy over $544 million in the claims. Earlier this month, the company said it would halt work on the project April 12.

The company said the Navy agreed to make provisional eleminate the programs negative cash flow for two months.

Food Fair Inc. of Philadephia, the supermarket chain, said it enjoyed a turnaround in its financial results for the second quarter, erasing a first-quarter loss of nearly $2 million to post a $2.5 million (34 cents a share) profit on sales of $679.73 million.

The second quarter figures compare with earnings of $3.07 million (42 cents) for the same period a year ago on sales of $586.72 million.