Hilton, 25, was arrested Sept. 7 just after midnight for driving erratically in her silver Mercedes-Benz SLR McLaren in Hollywood, according to the LAPD.

She scored a .08 on a Breathalyzer, the minimum blood-alcohol level to qualify as a DUI reports People Magazine.

After the arrest, Hilton told KIIS-FM radio in Los Angeles that she had been to a fund-raising party after a long day shooting a music video and had just one drink.

"I had one margarita (and) was starving because I had not eaten all day. Maybe I was speeding a little bit and I got pulled over," Hilton told the radio station.

"I was just really hungry and I wanted to have an In-N-Out Burger," she said, referring to the popular, California-based fast-food chain.

"I just spoke with Paris an hour ago, and she's happy the matter is behind her," Hilton's rep, Elliot Mintz, tells PEOPLE.

"We believe this was an appropriate resolution given the facts in this matter and both sides' desire to avoid a trial on the original charges," says Hilton's attorney, Howard Weitzman, who is also representing Nicole Richie in her pending DUI case.

Two weeks ago, the heiress pleaded not guilty to two misdemeanor counts of DUI and driving with a blood-alcohol level of .08 or higher.