# Dear Dirichlet, Issue 16

Girl guides, cooking, and public transport find their way into the prof’s postbox this issue.

Moonlighting agony uncle Professor Dirichlet answers your personal problems. Want the prof’s help? Send your problems to deardirichlet@chalkdustmagazine.com.

### Dear Dirichlet,

When I was growing up, I really enjoyed being part of the Girl Guides, so I’ve recently signed my eight-year-old daughter up to the local unit for under-10s. I think she’s having lots of fun but now I can’t stop her wandering off randomly every time we go out. She’s not very quick but I’m just worried she’s going to get herself seriously lost… aren’t they supposed to be learning orienteering or something?

Dirichlet says:

Whatever you do, do not buy her flying lessons! If my suspicions are correct, in 2D I guarantee she will always come home (Polya’s recurrence theorem) but in 3D there is no hope! Why do I say this? Small steps, random walks… I’m afraid you’ve got yourself a Brownie-in-motion.

### Dear Dirichlet,

In preparation for going away to uni, I’ve been taking cooking classes over the summer. I’m going to buy some pots and pans next weekend but my halls room has limited storage and I’m worried about getting a big enough pan which won’t take up all the space. Know any good recipes for small pots?

— Blanche Talmonds, Worcester

Dirichlet says:

Funnily enough, I have the perfect recipe to solve both of your problems. Take all your existing recipes and place them in order of size. Now buy the smallest pan that’s bigger than everything you want to cook. That’s it! I call it lim soup’. (Salt quanto basta.)

### Dear Dirichlet,

They don’t half have some strange designs for public transport vehicles these days. I see the 253 is no longer a New Routemaster, but has been given a sharp pointy nose at the front and back, a bit like a ship. Is this aerodynamics? My only trip on it ended in disaster when, turning a tight corner, the front nose took out a traffic light. Needless to say I walked home.

— Oyster lover, London

Dirichlet says:

Sounds like you got on the rhombus! Diamond-time again I have written to bus designers offering my expertise just for my letters be obtusely ignored. Kite frankly — and we shouldn’t go (trap)ezi-on-um — at least without the nose they have what they should’ve started with: a wrecked angle. Although I don’t ask square this happened, I think in Manchester they do it well — I always hype up (n)arrow-yellow-trams.

### Dear Dirichlet,

My niece got her GCSE results back last week and I am thrilled to say they are good… probably? Honestly I can’t tell any more, they’re just a bunch of numbers. Can you tell me what they mean in terms of the letters we’re used to? (See attached.)

— Ed Agsell, Wrotham

Dirichlet says:

I can confirm that the numbers attached do not form a valid credit card number or a sequence from the TV show Lost. Stand in an open space and rotate anti-clockwise. Now ask your niece to hold her results sheet and to walk clockwise around you. If you now look at the marksheet as it passes, aha! ABCs as promised! A simple consequence of a retro grade’ orbit.

### Dear Dirichlet,

A fancy brunch bar has opened up next door and they’re offering UCNCF with GESG. Any ideas? Otherwise I’ll just order the toast.

— Colin Door, Framwellgate Moor

Dirichlet says:

That’ll be Caesar salad with scrambled eggs. Bit weird.

## Heed Professor Dirichlet’s previous advice:

• ### Read Issue 19 now!

Drinks orders, integer mysteries and the new LMS president feature in our SS24 issue! Plus all your favourite puzzles & columns.
• ### Dear Dirichlet, Issue 19

Game shows, flight and social media bots are among the problems solved in this issue's Dear Dirichlet agony aunt column
• ### Prize crossnumber, Issue 19

Can you solve it?
• ### Which houseplant are you?

Find out by following our simple flowchart
• ### Poetry corner

Thankfully not by Torquil Farquhar de Smith
• ### Top ten: Mathematical norms

The undisputed chart of the best mathematical norms this season