In total, I made about $25,000 over two seasons.

I hadn't done any sports betting at all until I learned that it was legal in Colorado.

I started doing the match betting kind of at the prime time of all of these sportsbooks coming and really trying to hook us.

Join today, and get your first bet risk free up to $500.

Head to the DraftKings sportsbook app to claim your free bet.

Sign up now, and get five second chance bets up to $100 each.

And I just then took advantage of that in the sense of making very methodical choices on how I match their promos.

I joined all of the ones that were available in Colorado.

At the time, there were probably around 20.

I'm Maribeth Oscamou.

I am an associate teaching professor in the Department of Computer Science here at CU Boulder.

What I ended up doing was teaching four of my girlfriends that knew no math whatsoever how to do this, and they netted a couple thousand, just with 2 or 3 promos.

Theres a variety of different w you can do what are called mathematically advantageous bets.

One of the first ones is just called “match betting,” where you just bet on all possible outcomes of a given game.

So you pick different sportsbooks and maybe bet that Team A wins on this one, and Team B wins on this one for the same game.

Just doing that straight up is not going to be advantageous to you.

You're going to lose money because you're basically going to be paying them a little fee to bet every time you're doing it.

But what I learned was when they're trying to get you to join a sportsbook, they'll usually offer you a promotion.

And if you use that promotion to then set bets that are matched, you can guarantee a profit using that promotion bet.

This is assuming you have a bonus bet.

You have $200.

You can bet it and then they'll give you back just the profit.

Suppose I have Sportsbook A, Sportsbook B. Here's two different games, Houston versus Duke.

And I'm looking at these moneyline odds.

I would then pick the larger.

This positive ones 220, this one's 215.

So I'm going to use 220, meaning I'm going to bet Houston on this site.

And then I'm going to bet Duke on the other site.

My free bet, or my bonus bet, Im betting that $200 on this +220.

Then I can go back to my calculation from the other page and see exactly how much I need to hedge on Duke.

I bet my $200 bonus bet on Houston with my odds of +220.

Then how do I know how much to bet on Duke?

This is where I can go back to my formula.

If you plug all of that in, you're going to get 319.

So I'm going to bet $319 on Duke.

And you can see either way if Houston wins, I get a net of $121.

If Duke wins, I get basically the same.

Either way, I'm making $121 out of my original 200 free bet that I was given, my bonus bet.

That's what I've been calling my conversion rate.

That's roughly 60%.

The biggest takeaway I kept telling my students when we talked about probability and games of chance is like, these are designed to take your money, and it feels fun because there's this variance in it, but if you look mathematically how they designed this over time, it is for you to lose.

You could argue that I've never really gambled in the sense that I've never had variance and risk.

I would say matched betting is less profitable now because the promos aren't as big.

So you can come in and do this in Colorado with match betting, you're not going to make $25,000 doing it.

And now there's websites that will literally say, “Oh, tell me how much your bet is worth, and we can point out for you which odds would be the best currently.

For me, it was fun to use my love of math and then apply it towards an area that I enjoy watching, but without any of the risk.