Matt Parker - Humble Pi: A Comedy of Maths Errors

Originally a maths teacher from Australia, Matt Parker now lives in Godalming in a house full of almost every retro video-game console ever made. He is fluent in binary and could write your name in a sequence of noughts and ones in seconds. He loves doing maths and stand-up, often simultaneously. When hes not working as the Public Engagement in Mathematics Fellow at Queen Mary University of London, hes performing in sold-out live comedy shows, spreading his love of maths via TV and radio, or converting photographs into Excel spreadsheets. He is the author of Things to Make and Do in the Fourth Dimension.

Dedicated to my relentlessly supportive wife, Lucie.

Yes, I appreciate that dedicating a book about mistakes to your wife is itself a bit of a mistake.

Unless otherwise stated below, illustrations are copyright of the author and courtesy of Al Richardson and Adam Robinson. The author has endeavoured to identify copyright holders and obtain their permission for the use of copyright material. The publisher welcomes notification of any additions or corrections for any future reprints.

: The Tacoma Narrows Bridge Collapse Barney Elliott

: Sydney Harbour Bridge by Sam Hood Alamy ref. DY0HH0

: Torus ball Tim Waskett

: Manchester gears, 3D Sabetta Matsumoto

: North American Union concept on gears Alamy ref. G3YYEF

: Cogs and figures Dreamstime ref. 16845088

: High-five Dreamstime ref. 54426376

: Donna and Alex Voutsinas Family

: Kate and Chris Catriona Reeves

, Sumerian counting system and clay table, from Hans Jrg Nissen: Peter Damerow, Robert Englund and Paul Larsen, Archaic Bookkeeping: Early Writing and Techniques of Economic Administration in the Ancient Near East, University of Chicago Press, 1993.

: Laser units on rooftop Claudio Papapietro

NASA ref. STScI-1994-01

, How average are you? Defense Technical Information Center

: Average man calculations, from Gilbert S. Daniels (1952) The Average Man? Wright Air Development Center.

: ERNIE National Savings and Investments

: Lava lamps at Cloudfare Martin J. Levy

: Quebec Bridge, 1907 and Quebec Bridge, 1907, following collapse Alamy ref. FFAW5X and FFAWD3

In 1995 Pepsi ran a promotion where people could collect Pepsi Points and then trade them in for Pepsi Stuff. A T-shirt was 75 points, sunglasses were 175 points and there was even a leather jacket for 1,450 points. Wearing all three at once would get you some serious 90s points. The TV commercial where they advertised the points-for-stuff concept featured someone doing exactly that.

But the people making the commercial wanted to end it on some zany bit of classic Pepsi craziness. So wearing the T-shirt, shades and leather jacket, the ad protagonist flies his Harrier Jet to school. Apparently, this military aircraft could be yours for 7 million Pepsi Points.

The joke is simple enough: they took the idea behind Pepsi Points and extrapolated it until it was ridiculous. Solid comedy writing. But then they seemingly didnt do the maths. Seven million sure does sound like a big number, but I dont think the team creating the ad bothered to run the numbers and check it was definitely big enough.

But someone else did. At the time, each AV-8 Harrier II Jump Jet brought into action cost the United States Marine Corps over $20 million and, thankfully, there is a simple way to convert between USD and PP: Pepsi would let anyone buy additional points for 10 cents each. Now, Im not familiar with the market for second-hand military aircraft, but a price of $700,000 on a $20 million aircraft sounds like a good investment. As it did to John Leonard, who tried to cash in on this.

And it was not just a lame tried. He went all in. The promotion required that people claimed with an original order form from the Pepsi Stuff catalogue, traded a minimum of fifteen original Pepsi Points and included a cheque to cover the cost of any additional points required, plus $10 for shipping and handling. John did all of that. He used an original form, he collected fifteen points from Pepsi products and he put $700,008.50 into escrow with his attorneys to back the cheque. The guy actually raised the money! He was serious.

Pepsi initially refused his claim: The Harrier jet in the Pepsi commercial is fanciful and is simply included to create a humorous and entertaining ad. But Leonard was already lawyered up and ready to fight. His attorneys fired back with This is a formal demand that you honor your commitment and make immediate arrangements to transfer the new Harrier jet to our client. Pepsi didnt budge. Leonard sued, and it went to court.

The case involved a lot of discussion over whether the commercial in question was obviously a joke or if someone could conceivably take it seriously. The official notes from the judge acknowledge how ridiculous this is about to become: Plaintiffs insistence that the commercial appears to be a serious offer requires the Court to explain why the commercial is funny. Explaining why a joke is funny is a daunting task.

But they give it a go!

The teenagers comment that flying a Harrier Jet to school sure beats the bus evinces an improbably insouciant attitude toward the relative difficulty and danger of piloting a fighter plane in a residential area, as opposed to taking public transportation.

No school would provide landing space for a students fighter jet, or condone the disruption the jets use would cause.

In light of the Harrier Jets well-documented function in attacking and destroying surface and air targets, armed reconnaissance and air interdiction, and offensive and defensive anti-aircraft warfare, depiction of such a jet as a way to get to school in the morning is clearly not serious.

Leonard never got his jet and Leonard v. Pepsico, Inc. is now a part of legal history. I, personally, find it reassuring that, if I say anything which I characterize as zany humor, there is legal precedent to protect me from people who take it seriously. And if anyone has a problem with that, simply collect enough Parker Points for a free photo of me not caring (postage and handling charges may apply).

Pepsi took active steps to protect itself from future problems and re-released the ad with the Harrier increased in value to 700 million Pepsi Points. I find it amazing that they did not choose this big number in the first place. Its not like 7 million was funnier; the company just didnt bother to do the maths when choosing an arbitrary large number.

As humans, we are not good at judging the size of large numbers. And even when we know one is bigger than another, we dont appreciate the size of the difference. I had to go on the BBC News in 2012 to explain how big a trillion is. The UK debt had just gone over 1 trillion and they wheeled me out to explain that that is a big number. Apparently, shouting, Its really big, now back to you in the studio! was insufficient, so I had to give an example.

I went with my favourite method of comparing big numbers to time. We know a million, a billion and a trillion are different sizes, but we often dont appreciate the staggering increases between them. A million seconds from now is just shy of eleven days and fourteen hours. Not so bad. I could wait that long. Its within two weeks. A billion seconds is over thirty-one years.