Marriott Corp. yesterday reported a 23 percent increase in profits for the third quarter and said it is showing strong gains in its restaurant and hotel operations and lesser gains in its theme-park and contract-food service divisions.

Marriott earned $36.7 million ($1.32 a share) on revenues of $747.2 million in the three months ended Sept. 30, compared with a net income of $29.9 million ($1.10) on sales of $631.6 million in the same period a year earlier.

For the first nine months of its fiscal year, net climbed to $84.2 million ($3.03) from $69.2 million ($2.54) and sales were up to $2.1 billion from $1.75 billion.

Marriott executives said the 18 percent increase in revenues for the quarter and the 19 percent gain for the year so far reflected improvements in all the company's major lines of business.

"We expect continued solid improvement in our results for the fourth quarter and the full year as America's economic recovery is more fully reflected in our markets," said President J.W. Marriott Jr.

Sales of Marriott's restaurants jumped 25 percent and profits climbed 38 percent, largely because the Roy Rogers division has added 79 new units, most of them Gino's locations that were acquired by Marriott.

Contract-food service sales were up 14 percent and operating earnings up 17 percent as the result of gains in both in-flight airline food service and airport terminal operations. Even Marriott's Great America theme parks--the company's weakest division--showed a seven percent increase in revenues and what the company called "significant" increases in profits.