The woman who purchased the sole winning Powerball ticket has been identified as 53-year-old Mavis L. Wanczyk from Chicopee, Mass., who came forward Thursday to claim her winnings.

Wanczyk purchased the winning Powerball ticket at the Pride Station & Store in Chicopee. She becomes the winner of the largest single-ticket Powerball jackpot in history.

Wanczyk, a mother of a daughter and son, says she chose the winning numbers based on her family's birthdays. She says she does not plan to return to her job at a local hospital. She appeared at a press conference with officials from the Massachusetts State Lottery on Thursday afternoon.

During the press conference, Wanczyk told reporters she found out she had won the jackpot as she was leaving work Wednesday night with a colleague.

"He's reading these numbers, and I pull mine out, and I go, 'Hey, I have that number. And I have that -- I have that!'" she told reporters. "And he goes, 'Let me see that ticket. You just won!'"

The numbers she chose were based off the birthdays of family members and an assortment of random selections, Wanczyk said.

"My numbers were kind of basically random, like maybe with our birthdays, one from here, one from there," she said. "There's a thing between me and my mom and my stepfather and I have a friend, we all go out to dinner on a Friday night and we play Keno, and our number is four. I just happened to choose, and it worked to my advantage."

Wanczyk said the first thing she'll do is take some time off.

"I just want to sit back and relax," Wanczyk said. "I had a pipe dream, and my pipe dream has finally come true. I wanted to retire and it came early."

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