# You're reading: Posts Tagged: lottery

### An incorrect model of the lottery, and when it doesn’t matter

Recently I came across an interesting idea about little mistakes in counting problems that actually don’t amount to much. In A Problem Squared 030, Matt Parker was investigating the question “What are the odds of having the same child twice?” and made some simplifying assumptions when thinking about DNA combinatorics. He justified leaving out a small number of things when counting an astronomical number of things by going through an example from the lottery.

The current UK lottery uses 59 balls and draws 6 of these, so the one in 45 million figure arises from $$\binom{59}{6}=45,\!057,\!474$$, and the probability of winning is a tiny

$\frac{1}{45057474} = 0.00000002219387620 \text{.}$

Matt posits the idea that somewhere along the way we forget to include some tickets.

But let’s say along the way while I’m working it out, for strange reasons I go ‘oh you know what, I’m going to ignore all the options which are all square numbers. You know, I just can’t be bothered including them. Yeah, they’re legitimate lottery tickets, but just to make the maths easier I’m going to ignore them’. And people are getting up in arms, and they’re like ‘you can’t ignore them, they’re real options’.

### Mathematical Objects: Lottery machine

A conversation about mathematics inspired by a lottery machine. Presented by Katie Steckles and Peter Rowlett.

### Relatively Prime is back!

Aperiodipal numero uno Samuel Hansen’s acclaimed podcast series Relatively Prime is back, on a new monthly schedule, with an episode about how PhD student Ibrahim Sharif designed a lottery to award licences to sell cannabis in the state of Washington.

When the stakes are so high (geddit?! – Ed.) you have to be really sure that your lottery is fair. That’s where a lot of fun maths comes in.

You can listen to Lottery Daze on relprime.com. Sam intends to fund this new incarnation of Relatively Prime through Patreon – you can pledge to pay Sam a certain amount (starting at a dollar) for every episode he releases, with perks for paying more such as a postcard from Sam or placing an ad in one of the episodes.

Listen to Lottery Daze on relprime.com

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