Sales of manufactured goods rose 1.1 percent in November, the strongest increase in six months, and the pace of inventory growth slowed, providing more evidence that the economy may be on the rebound.

In a separate report, the Federal Reserve Board reported that the operating rate at the nation's factories, mines and utilities rose 0.3 percentage points to 81.9 percent in December, still below the peak of 82.7 percent reached last July. For the year, the operating rate averaged 81.6 percent, compared with the 82.4 percent average between 1967 and 1982.

Combined with recent reports of a strong rise in industrial production last month, yesterday's statistics point toward renewed energy in the economy, economists said.

"I think it's further evidence that the economy has revived from its summer slump or late summer slump," said Alan Murray, an economist with Citicorp Information Services.

Last summer, demand for domestic goods suddenly stopped, leaving businesses with unwanted inventories. Those inventories forced manufacturers to reduce production, which led to a drop in factory output and capacity utilization during the fall. Industrial production declined in September and October.

Part of the reason for the decline in domestic activity was that purchasers bought more imports, and some pent-up demand by consumers had been satisfied during the first half of the year, economists said.

However, interest rates have declined for several months, providing incentives for some businesses and consumers to renew buying although at a lower level than experienced at the same time last year.

The slower increase in inventories and pickup in sales is "healthy as far as growth for the future goes," Murray said. "If sales keep rising, inventories are going to have to keep rising too. That will mean not only will manufacturers of goods be increasing production and employment, but also manufacturers of materials" because their products "go into other people's inventories."

Manufacturer's sales rose $4.4 billion in November from October and were 7.4 percent above the level in November 1983, the Commerce Department said. Total durable goods sales rose 1.1 percent in November and 11.4 percent above the previous November, Commerce said.

The largest durable goods sales increase was chalked up by retailers, whose sales rose 2.3 percent. Sales by manufacturers rose 1.3 percent, and those of wholesalers were unchanged.

Total nondurable goods increased 1.1 percent in November and 4.2 percent from November 1983, Commerce said. Nondurable goods sales of retailers increased 1.8 percent, and those of wholesalers rose 1.3 percent. Sales for manufacturers of nondurables increased 0.4 percent.

Inventories were virtually unchanged, increasing 0.07 percent in November.

Meanwhile, the operating rate for manufacturers was 82.2 percent in December, above the 1967-1982 average of 81.8 percent. The operating rate for mining was 76.2 percent in December, up from 75.4 percent in November, and the rate for utilities was 81.7 percent in December, a decline from 82.7 percent the previous month.

Capacity utilization figures are below the mid-1984 levels because of the decline in production and because many businesses have bought goods from abroad, leaving some unused capacity at home. In addition, businesses have invested in plant and equipment to increase capacity.

Economists say that if capacity utilization exceeds about 84 percent, it could produce shortages and bottlenecks that could lead to accelerated inflation.

"We still have a good bit of slack there," Murray said. "Our forecast is that the expansion of the economy may be relatively moderate so that capacity utilization figures will rise only gradually" in 1985.