The price on the average-equipped 1979 Chrysler Corp. car will be $273 or 4.2 percent higher than on the last 1978 models, the No. 3 automaker announced yesterday.

The increase is comparable to those announced earlier by General Motors Corp. and Ford Motor Co.

The new prices "are in line with President Carter's effort to achieve deceleration of price increases," Chrysler said in a statement.

Ford and GM increased prices 4.1 percent on their average-equipped cars. American Motors Corp. posted a 4.6 percent hike.

The increases are smaller than in recent years. But the industry has said it will probably make small increases during the model year in what has been dubbed a "nibble-bibble" pricing policy.

The goal is to achieve "deceleration" of prices to combat inflation. Ford has vowed to keep the total model-year increases to within 5.5 percent.

A year ago, increases on the new 1978 models were between 5.5 percent and 6 percent. Those were followed by numerous increases in small-car prices and across-the-board price boosts of 1.3 percent to 1.4 percent.

The "average-equipped" figure is the suggested retail price on cars with the most common package of options.

Chrysler said the auto industry "consistently has led the nation in price restraint" and that car prices "have risen at a far lower rate than the consumer price index over the years."