a mysterious multimillionare named joan ginther with such a low profile that this 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 dents 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.ot of tickets all the time. she'd buy the whole roll. >> her passion was scratchoffs. tip so everyone was excited. >> luck just followed her. >> reporter: well, it certainly raised a lot of eyebrows. >> reporter: journalist peter mucha was intrigued enoughover 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 kets from the tiny store. >> if you buy a hell of a lot of more and if you keep ordering you'll have all these tickets coming to the same place.ling 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 th

we tried friends, neighbors, and -- >> i'm hoping to speak to someone named joan ginther. >> reporter: even her 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 of the mit students who learned 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 seve