Transcript for 7-Time Lottery Winner Reveals How to Increase Chances of Winning: Part 3
? It's easy to overlook. The small, dusty rundown town of bishop, Texas, population 3,000. But it may be one of the luckiest places on Earth, at least for one lottery winner who bought four winning tickets in the area, two at this now boarded up mini mart. Her total wins? More than $22 million. There are people who have won more money, but there aren't people who have beaten the odds repeatedly like that. Reporter: The odds? 1 in 18 septillion. That's an 18 with a whopping 24 zeros after it. 18 septillion is about the number of raindrops that have ever fallen in the history of the Earth. Reporter: And who is the odds defying winner? A mysterious multimillionare named Joan Ginther with such a low profile that this 47-year-old yearbook photo is all we could find. Reporter: Nobody even knows what she looks like. It's like she's a unicorn. Reporter: She grew up in bishop, and residents say she would return twice a year staying at bishop's only motel, just steps from the times market, sometimes for months at a time. She'd buy a lot of tickets all the time. She'd buy the whole roll. Her passion was scratchoffs. She always give $20 tip so everyone was excited. Luck just followed her. Reporter: Well, it certainly raised a lot of eyebrows. Reporter: Journalist peter Mucha was intrigued enough to start poring over lottery records, for a series for philly.com. What he found was not lady luck, but a lady who seemed to know exactly what she was doing. Buying massive quantities of scratch-off tickets from the tiny store. If you buy a hell of a lot of tickets the lottery will send more and if you keep ordering you'll have all these tickets coming to the same place. Reporter: Funneling so many tickets to one place, increasing the chance the winning one would end up there. There was a week in 2009, when the lottery sent 20% of all the tickets in Texas to the times market in bishop. It was a $10 million scratch-off game and Ginther won. Reporter: She was leveraging very dramatically, increasing her odds. Reporter: Even though there's no evidence that what Joan Ginther did is criminal, she's made herself impossible to find. We tried friends, neighbors, and -- I'm hoping to speak to someone named Joan Ginther. Reporter: Even her former college, that would be Stanford university where she just so happens to have a ph.d. In none other than mathematics. Coincidence? Probably not. When it comes to outsmarting the lottery, it helps to be a math genius. We're counting cards, woo's not gambling. Reporter: You may have heard of the mit students who learned to count cards, depicted in the movie "21." You may not have heard of James Harvey, an mit senior who noticed a quirk in a Massachusetts lottery game named cash winfall. The goal in this game, match six random Numbers and win the jackpot. And if the jackpot got to $2 million and nobody won, it would roll down or split between anyone who matched just three, four or five Numbers. Harvey realized he was virtually guaranteed a profit if he bought enough tickets and typed it perfectly to the roll-down so Harvey along with a group of mit students bought a massive amount. They bought 700,000 tickets. It cost them $1.4 million. They worked with four different convenience stores. The stores would stay open all night. This went on for seven years and they did this full time. This was their job. Yeah. Eventually they made a total of more than $3.5 million profit by doing this. Reporter: $3.5 million. $3.5 million. Reporter: Until finally "The Boston globe" wrote an expose and Gregory Sullivan, the former inspector general, was asked to investigate. Do you think it was cheating? When the government investigated it, they found that it was legal. Reporter: We rolled the dice and asked the mit gang for an interview, but all bets were off. But not all repeat lottery winners are quite so elusive. Richard Lustig says he knows how to game the games and he'll tell anybody who wants to listen. Increase your chances of winning more often and larger amounts of money. Luck has nothing to do with it. It's not something by chance. More money than most people will ever see in a lifetime. Reporter: You have won the lottery many times. I've won seven lottery game grand prizes. No one in the world has ever done that. Grand prize win number seven. And that was 98,900 and change. Almost $99,000. Reporter: Lustig's made over a million in the Florida lottery with the seven biggest wins ranging from $10,000 to more than $800,000. What did you buy with your winnings? I bought a jag. A jaguar. Yeah, drive in style. I bought a Harley. I bought my son his first car and what is he driving? A beamer. My wife and I have gone on dozens of cruises, you know. Reporter: Lustig says he relies not on luck but on a method he touts in a book aptly titled "Learn how to increase your chances of winning the lottery." So what's your method? It's a lot of things that you have to do. Reporter: One tip, he says when you pick your Numbers, don't just use dates. Most pick birthcase or anniversaries so all the Numbers they play are going to be between 1 and 31. So what you're doing is you're actually decreasing your chances of winning. Reporter: Also, if you lose don't throw out your ticket. Some lotteries have second chance drawings that offer big bucks. And he says, don't rely on computers to draw random Numbers for you. Don't buy quick picks. Reporter: Why? You're more likely to win something if you pick your own. Reporter: But most lottery experts disagree. We asked Aaron Abrams, a math professor at Washington and lee university. Quick picks produce randomly chosen Numbers. And those Numbers should be no better or worse than any other Numbers. Reporter: And what about Lustig's advice to avoid using dates? If you want to avoid sharing a jackpot, you're better off probably choosing larger Numbers than 31. But choosing large Numbers will not affect your chances of winning. A lot of people say your method is bizarre. One quote is, "Richard Lustig is a get-rich-quick hack with no idea at all how to beat any lottery." How do you respond to that? If they've never won even one time, are you gonna listen to them or are you gonna listen to me, who's won seven times? Reporter: Maybe you're just really, really lucky. Oh, come on. People who say that, how can anybody seriously believe that I won seven times just because I'm lucky? Reporter: Lustig has played the lottery every single day for more than 20 years, which begs the question. So how much money do you think you've spent on lottery tickets? I have no way of knowing. I never kept track. Reporter: Are you breaking even? Are you sure you've made money? I'm ahead. I'm ahead. Reporter: How far ahead? I don't know how far ahead. Believe me. Reporter: Why are you sure you are then? Because I'm not digging into my pocket. I'm doing something that no one has ever done before. That's billion with a "B." Reporter: Then how come you haven't won the big lottery? I hope you have your tickets. Good luck. It just has not been my turn yet, I guess.
This transcript has been automatically generated and may not be 100% accurate.