Vice President Mondale predicted yesterday that the ferderal government will better corrdinate fiscal and monetary policy now that G. William Miller is chairman of the Federal Reserve Board.

President Carter's decision to reduce the size of his tax cut proposal was made in part because of Miller's counsel that he "could be more accommodating on the monetary side" if fiscal pressures on the economy were reduced, Mondale told the economics club of New York.

The vice president said he is encouraged by initial responses to the administration's appeal for the voluntary measures by business and labor to restrain price and wage increases.

He said the automobile and aluminum industries had made commitments to slow the rate of price increases and he cited statements of support from the National Association of Home-builders and National Retail Federation.

Mondale reinterated the administration's opposition to mandatory wage and price controls.

"From business we expect moderation. From labor we expect comparable wage restraint," he said in a luncheon speech.

The process of fighting inflation. Mondale said, will be painful but the administration relies on the patriotism and good sense of business an labor and the support of all people.

He predicted that a sound energy bill and tax cut proposal would emerge this year from Congress.

Mondale ducked a question from the audience of business executives about President Carter's proposal to make only half the cost of business lunches tax deductible.

Asked whether he would favor extending Carter's idea to the luncheon he was addressing, Mondale replied: "Only if you've had three martins."