Hello, this is more or less on the BBC World Service.

I would like to extend a heartfelt welcome to you all.

I'm Tim Harford and we're your weekly guide to the numbers all around us in the news,

in life, and this week on Netflix.

If you recognise that voice, you'll know we're talking about Squid Game, the South Korean

drama in which 456 financially desperate contestants play children's games against each other.

The reward for the winner is 45.6 billion Korean won or 38.6 million US dollars.

For everyone else, the consolation prize is death.

In fact, Netflix announced that the show was its most popular, having been viewed by more

than 140 million people, or rather 140 million Netflix accounts.

We'll be looking at that later, but first we need to help out a loyal listener.

They want our help in understanding the numbers behind one of Squid Games' deadly contests.

And there are very, very minor spoilers coming up.

Now.

One of the games they play involves stepping across a bridge.

To move forward, they must leap onto one of the two tiles in front of them.

One tile will hold their weight, while the other will break and send them falling to their

death.

On average, how many players can we expect to survive?

To avoid revealing any twists, let's turn this into a puzzle with the same mathematical structure.

Imagine you're a video game player, you've got 16 lives, and you have to move along

an 18-step path.

...