**Number of the podcast:**1729, a fairly uninteresting number.- Sums of cubes updates:
- The Collatz conjecture:
- Numberblocks, Sumaze primary, and DragonBox
- GeoGebra
- Number of Core Maths students increased last year
- Pitching core maths?
- Reuben’s homework - Round three dice
**Puzzle feedback**: Gold star for Adam Atkinson who got 4/9 as P1’s win probability. I evaluated a double integral. Silver stars for our favourite listener in Carrom Downs, Australia, Sam Steele and @schwartzstack, who both gave the right answer for the wrong reasons (higher mean doesn’t mean more likely to win).**New Puzzle**: (via @david_cobac You have a 10 by 10 square grid. A number from 1 to 100 is selected and the corresponding square is coloured. This is repeated 100 times. On average, how many squares do you expect to be not coloured in?

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]]>We discuss:

- The Big Internet Math-Off. My favourite pitch wasn’t really in the contest!

I also liked Alex’s wobbly table and Anna’s FURNACE. **Number of the podcast**: 24.- The Winton Centre Quick Quiz for Legal Professionals from @dspiegel.
- Maths Scholarships
- The £50 note.
- The Maryam Mirzakhani Prize in Mathematics.
- The Isaac Newton Institute’s summer puzzles
- Eliasson exhibition at Tate Modern
- What has 4 letters, sometimes 9 letters, but never has 5 letters.
- A claim by Claire’s Accessories.
- Catriona Shearer’s book is available on Amazon: Geometry Puzzles in Felt Pen.
**Puzzle feedback from last time**: The average distance of two points in a unit square. No solutions received! (It’s 0.5214 ish, the result of a tricky double integral.)**New Puzzle**via @ghast_neoh: There are two players, and a machine that outputs a random number between 0.0 and 1.0 when you press a button (inclusive, chosen uniformly and independently, from the reals, etc). Player 1 pushes the button twice, and multiplies the two outputs together to get a score (e.g. 0.45 x 0.9=0.4). Then player 2 pushes the button once, and squares the result to get their score (e.g. 0.67 x 0.67 = 0.4489). The higher score wins. Which player wins more often?

- apparently there are caveats.

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]]>- The Big Internet Math Off and associated stickerbook
- 99 variations on a proof by Philip Ording
- The Art of Statistics - Learning from Data by David Spiegelhalter
- Maths on the back of an envelope - Rob Eastaway
- 1 in 8 men believe they “could” win a point against Serena Williams.
- Green number lines
- via Adam Atkinson: Zachtronics games are now free for school use. Also, "Baba is You" is fun.
- Mathematical objects podcast
- Via @peterrowlett: The Talking maths with your kids hashtag #tmwyk

- That said, I think @draon_dodo has been involved in two previously.

The post Wrong, But Useful: Episode 69 appeared first on Flying Colours Maths.

]]>We discuss…

**Number of the Podcast:**5- Are Fish and Chip shop owners good at maths?
- Two maths puns and a maths joke
- Are there ‘popular’ books that ‘lead you in’ to mechanics?
- An application of the sum-of-squares problem
- Via @PaulsPrattle (Paul O’Malley): “If you were the ruler of the universe tomorrow what would be the objective in secondary mathematics learning for all kids everywhere?”
- Via @aap03102, (Chris Smith)’s newsletter: some love for Simon Plouffe
- Via @christianp: The Big Mathoff is running again
**Puzzle feedback from last time**: We hadn’t seen any solutions when we started recording, but some have come in since - we’ll mention those next month. However: Chris pointed out a tweet from @mathsjem (Jo Morgan) showing the clock-hands puzzle in Thompson’s Practical Algebra, published in 1878.**New Puzzle**: There are 3 lighthouses. The first shines for 3 seconds and then is off for 3 seconds. The second shines for 4 seconds and then is off for 4 seconds. The third shines for 5 seconds and then is off for 5 seconds. Initially, all three come on together. When is the next time they’re all on at the same time?

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]]>- Sheena's
**Number of the Podcast**: 3,212 - Board Games - Number Fluxx, Prime Climb
- Magic: The Gathering is undecidable!
- Oxbridge
- Time surprises
- The oddness of the Fibonacci sequence
- The heights of women
- Big MathsJam Down Under
- Population modelling in the Marvel universe
- The IMU committee for women in mathematics newsletter
- Elwyn Berlekamp has died
- How do you see means?
- The Superpermutation Search
- Via Jeremy Cote: "I've actually seen [J] in a textbook I've used for my real analysis course, but in that case, it was to represent the natural numbers (1,2,3,...). The book is called Introduction to Analysis, and can be found here.
- Other maths podcasts: a list; MathsAt; MakeMathMoments.
**Puzzle feedback:**No stars of any description for the Crystal Maze problem.**New puzzle:**At 3:00, the hour and minute hands on a clock form a right angle. What is the next time that happens?

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]]>We discuss:

- LaTeX (time to fight again)
- Mathematical sign language
- More interesting ‘bad graphs’ than the obvious howlers you usually see on the internet.
- Via @peterrowlett: Some people think statistics has too much significance, and it’s hard to disagree.
- Chalkdust article by @loopspace about Catriona's other, almost-mathematical, hobby, bellringing!
- @mathsobjects, a new podcast from @stecks and @peterrowlett. Any other cases of mathematical discoveries that looked different at the time?
- Does your road have a house 13? 136 votes: yes 56%, no, not long enough 20%, no missed out 24%.
- Escape room advice - don’t use algebra
- (via @ProfSmudge) What’s $\frac{3}{4}$ of $\frac{2}{3}$ - is this surprising or obvious?
- Shapes with different shadows
- Stephen Wootton tweets: @WrongButUseful regarding tax there is also the interesting case between £100k - £120k where the tax free allowance is reclaimed thereby giving rise to an effective tax rate higher than the highest rate of income tax! Keep up the podcasts, thank you.
- via Adam Atkinson: a picture of a 24-hour clock (photo by Daniele Aurelio of Pavia Mathsjam)
- Adam found a book from the 50s or 60s which called the set of integers “J”. “Have you or your loyal listeners ever run into this?”
- @divbyzero asks: Technical math terms the general public uses in a nontechnical way: inflection point (a turning point), squaring the circle (difficult task of reconciling two very different things), in the Venn diagram of _ and _ (in the intersection of), exponential growth (grows fast). Others?
**Puzzle feedback from last time**:**This month’s puzzle**: In a game show, you have four distinct tokens you have to arrange in an unknown order. Every time you guess, you are told1 how many are in the correct position. What strategy gives you the correct answer in the fewest guesses?

- by way of FIRE

The post Wrong, But Useful: Episode 66 appeared first on Flying Colours Maths.

]]>- Chalkdust Issue 091 Fun spring cover with Harris spiral, Horoscope is back!, New academic webpage checklist (c.f. Colin’s old webpage, @standupmaths interview, top ten regulars, etc. Write for them!
- Talkdust, second best podcast: it’s about maths, puzzles, making the magazine, interviews.
**Number of the podcast**: 42. Sums of cubes and open questions- Pi day
- Apologies about audio last time. Dave’s fault.
- Superpermutations and Humble Pi
- Balancing pi on a beam
- One weird trick to deal with percentages
- The Queen Elizabeth Prize for Engineering for 2019 has been awarded to engineers Bradford Parkinson, James Spilker, Hugo Fruehauf and Richard Schwartz for their foundational contributions to the creation of GPS. The prize, worth £1,000,000, celebrates the global impact of engineering on humanity.
- Sumaze Primary, L; Martello Towers; Bloxors
- Dave is wrong about LaTeX

- It’s a magazine for the mathematically curious, apparently. Never heard of it.

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]]>*Apologies for the poor audio quality on this call. Dave's fault, obviously1 .*

We discuss:

- The Talkdust podcast
- (via Adam Atkinson): Life insurance
- Superpermutations: new record for n = 7 in the comments on a YouTube post
- @pecnut and @mscroggs have a LaTeX package that puts hats on things
- Desmos adding support for distributions and all sorts
- @mdawesmdawes’s QUIBANS website
- Dave has been playing the game The Mind
- (Via @peterrowlett), 318,000 combinations of pringles
- Dave gave a talk in Exeter and will hopefully give one in Bristol in June.
- Humble Pi by @standupmaths - book launch on March 2nd in London, tickets
~~selling fast~~sold out. You can join the waiting list here. - @honeypisquared (Lucy)’s new podcast - Mathematips
- We’ve been shouted out in @aap03102 (Chris Smith)’s newsletter, and on @missradders's padlet – thanks!
- Tax - round up or not?
- Rotationally symmetric equations (@robeastaway and @peterrowlett): here, here, and Elliot’s versions here
**Puzzle feedback from last time**: Gold star for @chrishazell72: for showing that $(a-b)^2 + (b-c)^2 + (c-a)^2 + (a+b+c)^2 = 3(a^2 +b^2 + c^2)$, and that the first child is 6, younger (2yo) born when elder was 3.**New Puzzle**(via @cmonMattTHINK): Find the line that touches $y= x^4 - x^3$ at two distinct points. Avoid calculus if possible.

* Edited 2019-02-13 to fix the title. Thanks, Adam.

- Narrator: it was not, in fact, Dave's fault.

The post Wrong, But Useful: Episode 64 appeared first on Flying Colours Maths.

]]>We discuss:

- Mathematical board games, including
**Number of the podcast**: Lucy doesn’t like numbers so we don’t have one.- Does your collection of maths people exclude anyone?
- Lucy went to Big MathsJam this year. Bowled over by the time taken to make sure people felt included. Clearly an intentional, thoughtful approach.

- Is stats actually maths1 ?
- Reference to Sara Hottinger - Inventing The Mathematician

- Christmas books:
- Colin - Factfulness by Hans Rosling
- Lucy - Perils of Perception by Bobby Duffy
- Dave - The Indisputable Existence of Santa Claus by Hannah Fry and Thomas Oleron Evans
- Some deserved applause for @fryrsquared’s Zeeman medal and @stecks’s appearance on QI

- Via Adam Atkinson - Money Box. £35 000 per year for life or £480 000 now?
- The great makeup heist
- Postal systems and nutri-grain
- Quick bits:
- New largest Mersenne prime: $2^{82,589,933} − 1$. Prizes listed here for any Mersennaries out there.
- via @christianp: Plouffe’s prime-generating function
- via @chrishazell72 - Sibahle Zwane ‘answers complex arithmetic questions in seconds’ (Is he as good as the article seems to think?)
- via @fenneklyra: Follow up on “Guess who”: There are 24 people on board, and I had a typo, the first question narrows it down to 12 which means it IS the most efficient one cause you will always have narrowed it down by half. Not sure it’s allowed
- via @peterrowlett: Thirdsday
- via @christianp: A lot of mathematical mortality recently – including Jean Bourgain, Peter Swinnerton-Dyer, Elias Stein and Sir Michael Atiyah.
- via @peterrowlett and @robeastaway: Rotationally symmetric equations. See also here and here
- via @fermatslibrary: Pizza

**Puzzle feedback**: @schwartstack and Adam Atkinson both found answers in the region of $3.5 \times 10^{38}$, rather than quadrillions. Gold stars all round. On looking into it more, the Fantasy Flight Games site claims 104 septillion (still several orders of magnitude too small.)**This month’s puzzle**: Prove that 3 times the sum of 3 squares is the sum of 4 squares.**This month’s second puzzle**: A parent buys a pack of 24 candles. On their first child’s first birthday, they use one candle; on the second, two candles and so on. At some point, a younger sibling arrives, and the candles are used in the same way. On one of the first child’s birthdays, the parent finds they have exactly the right number of candles left for that birthday. How old is the first child, and how old were they when their younger sibling was born?

* Edited 2019-01-15 to fix some of the links. Thanks to Adam Atkinson for pointing out the error.

- QTWTAIN

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]]>- Nira is a professional mathematical modeller, president-designate of the IMA, and a visiting fellow at Loughborough university.
- We discuss Nira’s entry in the Aperiodical Maths-Off. I mention a simulation of the Schelling model.
**Number of the podcast**: 2, the percentage of the top rate of National Insurance.- The Big MathsJam Special and Big MathsJam itself.
- Dave has a circle question that stumped his students. Nira turned the tables on some future teachers by making them simulate Aston Villa’s season. Ouch.
- A thread from @creeepyjoe about communication and collaboration – with an insight into Nira’s Mathematics Attack Room. Colin mentions the German €20 note, but meant the old DM10 note.
- @fenneklyra’s Guess Who questions: “White hair OR red hair OR glasses? Yes: Red hair or hat? No: Blond or hat? Then there are only 6 left of which you can make out the next question yourselves”
- @stecks was on @myfavethm to talk about the fold-and-cut theorem.
- Nira points to a tweet from @probabilityfact pointing out that 87% of Americans can be identified by the combination of ZIP code, sex and birth date.
- What’s the opposite of inside-out?
- @fotsn have put out a new audiovisual offering called
*You Can’t Polish A*.~~Nurse~~Nerd - Dave thanks Adam Atkinson for his help on percentages.
**Puzzle feedback**: gold stars for @schwartstack, @chrishazell and loyal antipodean listener Sam Steele, who each worked out $P(X=5) = \frac{1}{120}, P(X=4) = 0, P(X=3) = \frac{1}{12}, P(X=2) = \frac{1}{6}, P(X=1) = \frac{3}{8}, P(X=0) = \frac{11}{30}$.**This month’s puzzle**: Dave is playing Keyforge, in which a deck consists of 36 cards: twelve from each of three distinct clans. There are 51 distinct cards available for each clan (repeats are allowed), and seven clans. The makers quote quadrillions of possible decks; is this plausible?

In my Maths Attack Room recording a podcast with the @WrongButUseful Team. Love talking everything #mathematics. Thank you @icecolbeveridge for the invite! Look out for this episode next week. pic.twitter.com/4Ik04wsmds

— Dr Nira Chamberlain (@ch_nira) December 8, 2018

The post Wrong, But Useful: Episode 62 appeared first on Flying Colours Maths.

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