Just before this BBC podcast gets underway, here's something you may not know.

My name's Linda Davies and I Commission Podcasts for BBC Sounds.

As you'd expect, at the BBC we make podcasts of the very highest quality featuring the most knowledgeable

experts and genuinely engaging voices. What you may not know is that the BBC

makes podcasts about all kinds of things like pop stars,

poltergeist, cricket, and conspiracy theories and that's just a few examples.

If you'd like to discover something a little bit unexpected, find your next podcast over at BBC Sounds.

This is the BBC.

Thanks for downloading this podcast. This is the shorter World Service edition of more or less,

and this is a repeat of an episode we broadcast a few years ago. So very loyal listeners may

have heard it already. Enjoy.

Hello and welcome to more or less on the BBC World Service.

I'm Tim Harford.

This week, pregnancy due dates, but before that we'll hear from Matt Parker an unusual

combination of mathematician and stand-up comedian.

Matt recently wrote a book called Things to Make and Do in the Fourth Dimension.

It's a collection of tricks, games and puzzles that reveal bigger lessons about the world

around us.

Maths, says Matt, can even help you find the right life partner. So I laid myself

down on his couch and I opened my heart.

I'm pleased to say I'm happily married, but occasionally I have doubts as to whether maybe I settled down too soon.

Could I have done better if I waited? Seems unlikely but it's quite possible my wife could have done better if she had waited.

...