Most interior decorators would have been appalled to see how the Petrone family of Bowie spent $300 to furnish their living room. But the residents of 12204 Tilbury Lane couldn't have been more pleased with the $200 they spent for their 16 1/2-foot long, 4 inch wide "coffee table" or the additional $100 purchase of the royal blue mat which lies beneath it.

The wooden bar that fills the Petrone living room is a regulation balance beam for gymnastics competition. While the family of four must put up with the usual array of jibes from friends, the equipment offers Linda, 16, extra practice moments in her quest to become an Olympic gymnast for the Moscow Games of 1980.

Now in her fifth year of gymnastics, Linda has started to come into her own. After capturing the national YMCA champion in the floor exercise title, Linda swept all four individual events and the overall title in the Metro Championships held in Rockville on May 1. The 1976 Maryland high school champ in the uneven parallel bars and overall competition recently returned from the United States Gymnastics Federation May 26-8 in Phoenix senior national competition with sixth in the nation in the balance beam and 20th overall.

In the next six months, Linda will try to surmount her greatest obstacle by learning the difficult set of compulsory exercises she must master in order to graduate to the competition from which Olympians are chosen.

"I've met a lot of people and made a lot of friends," Linda explained of her 16 hours of practice each week. "It gives you real sense of satisfication to reach perfection or as close to perfection as possible."

Perfection is an important word to Linda. She likes to do well in all endeavors, as was evidenced by her straight-A average in her sophomore year at Elizabeth Seton High School.

However, despite admitting to "a vivid imagination," Linda remains modest about her successes and realistic about her chances to graduate into the level of the world's best gymnasts.

"It's good when you can set personal goals for yourself and accomplish them," said the 5-foot-4, 110-pound Petrone, "You like to set high goals, but you have to be realistic. If my best is the best, that's fine."

Linda said she gets "tired of hearing what color leotard Nadia (Commaneci, 1976 Olympic champ) wears," but appreciates the talent of the 15-year-old Rumanian and the interest she generated in the sport in the United States.

Linda is also glad there is not as much pressure in the United States as there is in the Communist nations. "In the United States, it's more like a hobby . . . If it looks like fun, you do it because you might have some fun," she said. "In the Communist bloc countries, they scouted her (Comaneci) in kindergarten and put her in a sports school."

Linda realizes gymnastics have caused her to miss much of the fun of her high school years but regards the rewards equal to the sacrifice. "It affects you - you miss a lot of things," she said. "I don't date as much as I might if I wasn't into gymnastics. But you have to know you priorities. It was my decision.

Gymnastics is a family event with the Petrones. Father Maurice handles most of the business affairs for Linda's club, the Docksiders of Annapolis, formerly the Parkettes South. Sister patty, 13,napolis, formerly the Parkettes South. Sister Patty, 13,ay is a USGF rated judge.

"When the girls became so involved, we started doing it as a family," said Mrs. Petrone. "Some families go to the lake together for the weekend.We spend the weekend together at the gym. We do it as a family."