ERJ Brainteasers Jan-June 2017

JUNE 2017

Great to see more new names appearing on our winners’ lists this month and there were several candidates in the running for our coveted top honour. However, for his stand-out performance in Week 2, our Brainiac of the Month award has to go to David Mann of SI Group in France.

Week 4: Odd one out

Which of these countries is the odd one out: Indonesia, Malaysia, Uganda, Kenya, Brazil, Colombia?

Answer: After one or two clues - line, map – to narrow down the options, some clever readers worked out the answer. First home was Zoë Baldwin, who identified Malaysia as the only one of these countries not crossed by the equator.

A big thanks to the many readers from around the world who replied during the week. Correct answers arrived in from, in the following order: Zoë Baldwin, marketing communication manager, Hankook Tyre UK Ltd, UK; David Mann, manager rubber technology, manager rubber technology, SI Group, Béthune, France;, France; Lars Linnemann, R&D manager, Genan A/S, Viborg, Denmark; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; John Bowen, consultant, Bromsgrove, Worcestershire; Alexander Mamikonyan, head of export dept, Empils-zinc Ltd, Russia; Fatima Bhatti, Polymer Access (Pvt) Ltd, Karachi, Pakistan

Week 3: Missing colour

Our question-setter was in a mean mood this week with a teaser that left even elite Brainiacs floundering. Thankfully, with a couple of much needed clues, a number of readers managed to identify the colour sequence of flags of Romania, Russia and Rwanda, with the missing colour yellow.

Thanks to everyone who battled this one and well done to: Stephen Fulton, R&D technology development manager, Umicore Specialty Materials Brugge NV, Brugge, Belgium;  Ralf Ortmayr, Toyo Tire, Germany; Zoë Baldwin, marketing communication manager, Hankook Tyre UK Ltd, UK; David Mann, manager rubber technology, SI Group, Béthune, France; John Bowen, consultant, Bromsgrove, Worcestershire, UK; Yuichi "Joe" Sano, Sumitomo Electric Industries, Ltd, Japan; Fatima Bhatti, Polymer Access (Pvt) Ltd, Karachi, Pakistan.

Week 2: Second guess

After a fairly full-on office party, Simon is heading home but can’t remember the second number in the simple security code on his bicycle lock. Can you help?

11,??, 29, 41

Answer: Amazingly there was only one clear winner David Mann, who recognised straight away Monday that this was a sequence of additive primes (numbers in which the digits also add up to prime numbers) and gave the correct answer 23. A second-place award goes to Amparo Botella who later in the week came up with the correct answer but then changed it to 19. Marks for effort should go to many others who came up with some wonderfully complex solutions to arrive at a different answer (mostly again 19, for some reason.)

Well done to: David Mann, manager rubber technology, SI Group, Béthune, France; Amparo Botella, Ismael Quesada S.A, Spain; Lars Linnemann, R&D manager, Genan A/S, Viborg, Denmark; John Bowen, consultant, Bromsgrove, Worcestershire; Fatima Bhatti, Polymer Access (Pvt) Ltd, Karachi, Pakistan; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Jessie Vukovic, Airboss, Canada; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Yuichi "Joe" Sano, Sumitomo Electric Industries, Ltd, Japan.

Week 1: Ian's walk

Rubber engineer Ian likes routines. Every day he leaves the office at 5pm, gets on a train that arrives at his local station at 6pm. His wife reaches there at exactly 6pm in a car, to pick him up. However, a power cut one day forced Ian to leave the office at 4pm and with the disruption he forgot to tell his wife.  He reached his local station at 5pm and started to walk towards home. Ian met his wife on the way as she was coming to pick him up at the usual time. They drove back to home. That day they reached home 20 minutes earlier than their usual time.

For how long, in minutes, did Ian walk?

Answer: The correct answer is 50 minutes. Well done to  John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Yuichi “Joe” Sano, Sumitomo Electric Industries, Ltd, Japan and Lars Linnemann, R&D manager, Genan A/S, Jegindøvej, Viborg, Denmark.

MAY 2017

As well as excellent and accurate answering, this month’s prize acknowledges that readers in some time zones get to open our Brainteaser a day or so later than others. So, not for the first time, well deserved congratulations go to Yuichi "Joe" Sano our new Brainiac of the Month>>

Question 4: Die hard

Dave and Bruce play a game with two dice on which the faces are painted red or green. Taking turns to throw, Dave wins when the two top faces are the same colour while Bruce wins when the colours are different. They each have an equal chance of winning. If the first die has 5 red faces and 1 green face, how many red and how many green faces are there on the other die?

Answer: The second die must have 3 red faces and 3 blue faces. Well done to: David Mann, manager rubber technology, SI Group, Béthune, France; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Yuichi "Joe" Sano, Sumitomo Electric Industries, Ltd, Japan.

Question 3: Sarah’s circle

First day on the job, so new rubber plant manager Sarah decides to introduce herself by gathering all the team around her in a circle. They are evenly spaced and the seventh person in the circle is directly opposite the 18th. How many people are there at the introduction meeting, altogether?

Answer: The official answer is 23 but our judges have decided to also accept 22 and 24, to allow for interpretations with or without Sarah. As Marzio Bussola explained: Because half of the circle is delimited by the distance between the 7th and the 18th persons, it means 11 places, so 22 people are altogether at the introduction meeting – plus Sarah.

Very well done to: John Bowen, consultant, Bromsgrove, Worcestershire, UK; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; Lars Linnemann, R&D manager, Genan A/S, Jegindøvej, Viborg, Denmark; Yuichi "Joe" Sano, Sumitomo Electric Industries, Ltd, Japan; Stephen Fulton, R&D technology development manager, Umicore Specialty Materials Brugge NV, Brugge, Belgium; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Ashley Croft, group supply chain director, Stapleton's (Tyre Services) Ltd, Letchworth Garden City, Hertfordshire, UK; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; - and everyone else who had a go.

Question 2: Floravision

How many plants or animals (real or imaginary) are on the official state flags of the 26 countries in the finals of Eurovision Song Contest last weekend? In case you did not see it, or maybe never heard of it, the finalists were: Portugal, Bulgaria, Moldova, Belgium, Sweden, Italy, Romania, Hungary, Australia, Norway, Netherlands, France, Croatia, Azerbaijan, United Kingdom, Austria, Belarus, Armenia, Greece, Denmark, Cyprus, Poland, Israel, Ukraine, Germany, Spain.

Answer: Moldova – eagle, aurochs (extinct wild cattle), and olive branch; Croatia – leopard (3), goat and pine marten; Cyprus – olive branches. (Note: After some debate, our judging panel controversially decided that the national flags of Austria, Poland and Spain were not those with coats of arms.)

Triple bonus points go, this week to Amparo Botella for: being first to reply; identifying the plant and animals on the flags (see below); and admitting that Spain deserved to come last in Eurovision (though, maybe, its song should have been joint-last with several others).

Our full winners list is: Amparo Botella, Ismael Quesada SA, Spain; John Bowen, consultant, Bromsgrove, Worcestershire, UK; Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami, Hyogo, Japan; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy.

Question 1: Game-changer

This time, readers were asked to identify our industry game-changer from the photo (below) with some clues given during the week:

Answer: The nice thing about our photo quizzes is that they usually produce a clear winner. This time the ‘extra well done’ goes to Marzio Bussola who recognised our industry trailblazer on Tuesday – a day ahead of anyone else. A shorter than usual winners list reads: Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; John Bowen, Bromsgrove, Worcestershire, UK; Amparo Botella, Ismael Quesada SA, Spain; Hugo Ernesto Vera, adscripto, proyectos expansión, FATE SAICI, Buenos Aires, Argentina; Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami, Hyogo, Japan.

Dr Otto Bayer (1902 -1982)

After obtaining his doctorate in chemistry at Frankfurt-am-Main University, Otto Bayer joined IG Farbenindustrie as a research chemist. In 1934, he became manager of the group’s central research laboratory in Leverkusen, Germany. There Bayer focused on macromolecular chemistry and his fascination with isocyanate reactions helped drive the development of urethane polymers. Over subsequent decades Bayer helped establish polyurethanes as a multi-million-tonne global industry that continues to grow today. In 1964, he became chairman of Bayer AG – a company co-founded in 1863 by Friedrich Bayer (no relation) and for a long time part of IG Fabern before becoming independent. He held the chairmanship for three years before retiring in 1967.

APRIL 2017

While many readers struggled with this month's questions, the judging panel had a relatively easy job in selecting a winner this time around. For being first out of the blocks almost every time and showing pinpoint accuracy, congratulations to John Bowen, the new Brainiac of the Month >>

Question 5: Missing numbers

What are the two missing numbers in the sequence below and why?

149, 162, 536, 496, 481, 1??

Answer: The next two numbers are: 0, 0. This is a series of squares: 1,4,9 are squares of 1,2,3 and so on up to 10 squared = 100. So well done to John Bowen, Bromsgrove, Worcestershire, UK; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Amparo Botella, Ismael Quesada S.A, Spain; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; Yuichi (Joe) Sano, Sumitomo Electric Industries, Ltd, Itami, Hyogo, Japan.

Question 4: Office code

On his final day at a rubber moulding company, the production engineer decided to play a trick on his colleagues by changing the office entry code – a series of four two-digit numbers. On their way to work the next Monday, his former colleagues received a text telling them that they could work out the code from the following series of numbers: 24 12 9 12 9 9 9 24 22 9 9 12 9 22. What was the new entry code?

Answer: This code-breaker proved more difficult than expected for many readers. The key was to recognise that the numbers referred to Roman numerals as per position in the alphabet. The code, so, was 41, 53, 17, 54 and congratulations for working this out to: John Bowen, Bromsgrove, Worcestershire, UK; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; and Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami Hyogo, Japan. Well done also to Liz O’Donovan, AAtyremaster, Dublin, Ireland; and Amparo Botella, Ismael Quesada SA, Spain, who were on the right track.

Question 3: Five from two

Using any combination of mathematical signs, symbols and functions, how can you make 5 from two 2s?

Answer: Well done, in order of receipt, to: John Bowen, consultant, Bromsgrove, Worcestershire, UK; Amparo Botella, Ismael Quesada SA, Spain; John D Burrows, consultant, France; Stephen Fulton, R&D technology development manager, Umicore Specialty Materials Brugge NV, Brugge Belgium; Jon Cutler, materials development manager, Trelleborg Sealing Solutions, Tewkesbury, UK; ; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy.

Question 2: Chemical challenge

Complete this sequence: CuSn3; Ag2...

Updated: Our question-setters may have complicated things  too much here by combining the chemical elements with the numbers as only three readers spotted the Olympics medal sequence of bronze, silver and gold (CuSn3, Ag2 and Au1). Well done to the trio on the podium: John Bowen, consultant, Bromsgrove, Worcestershire, UK; David Mann, manager rubber technology, SI Technology, Béthune, France; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand - and, of course, everyone else who took part.

Question 1 : Calendar Combo

Readers were asked to list the next three combinations in a sequence starting with Monday/2016, and then: Saturday/2020; Thursday/2024; and finally Tuesday/2028

Answer: Monday / 2016; Saturday / 2020; Thursday / 2024; Tuesday / 2028;   Sunday / 2032…Friday / 2036; Wednesday / 2040… etc

Always good to have a clear winner and well done to John Burrows for spotting that this was the run of Leap Year days (29 Feb) from the very first clue. Next came Liz O’Donovan, Amparo Botella, Thierry Montcalm and John Droogan on day 2. So, the full list of correct replies, in order of receipt, is: John D Burrows, consultant, France; Liz O’Donovan, AAtyremaster, Dublin, Ireland; Amparo Botella, Ismael Quesada SA, Spain; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; John Bowen, consultant, Bromsgrove, Worcestershire, UK; David Mann, manager rubber technology, SI Technology, Béthune, France; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; Karl Heinz Sandholzer, product management, vice president, Kempten, Saurer Germany GmbH & Co. KG, Germany; Sebastian Barbe, group operations manager, Hans W. Barbe Chemische Erzeugnisse GmbH, Wiesbaden, Germany.

MARCH 2017

We don't think there has ever been a back-to-back winner of our award but, for guessing common links and recognising part-images of scientists from our archives almost as soon as they were posted, there can only be one winner:

             Congratulations to David Mann of SI Group, who is once again the ERJ Brainiac of the Month >>

Question 5: Common people

This week, we posted pictures of four well-known people, asking: what is the common link between them?

Answer: This turned out more difficult than we expected for readers. The link was science: Pope Francis, Margaret Thatcher, Tony Tan and Angela Merkel were all scientists early in their careers before going on to world prominence in a different profession. As they might say 'you don't have to be a scientist to work here, but...'. Anyway, well done to: Michael Simpson, research & development engineer, Trelleborg Industrial AVS, Leicester, UK; David Mann, manager rubber technology, SI Group, Béthune, France; John Bowen, consultant, Bromsgrove, Worcestershire, UK; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada.

Question 4: I fought the lawn

It takes a gardener 90 minutes to mow a lawn measuring 200 metres by 300 metres. His next job is quite bigger, with the lawn measuring 600 metres squared, so he asks his son to help. Roughly how long will it take the pair to mow the lawn if the son works at 40% the speed of his father?

Answer: Making short work of this one, the answer (90x600x600/200/300/1.4) approximately 386 minutes came promptly in from: John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; David Mann, manager rubber technology, SI Group, Béthune, France; Jos Uijlenbroek, Ferm RFID Solutions, Zaltbommel, The Netherlands; John Bowen, consultant, Bromsgrove, Worcestershire, UK; Michael Simpson, research & development engineer, Trelleborg Industrial AVS, Leicester, UK; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; Bernd Pluimers, sales manager, SASCO Chemical Group LLC, USA; John D Burrows, consultant, France; Jon Cutler, materials development manager, Trelleborg Sealing Solutions Tewkesbury, UK; Aditya Biswas, design researcher, Daya Pursuit, Goa, India; Stephen Fulton, R&D technology development manager, Umicore Specialty Materials Brugge NV, Brugge, Belgium; Sergio Peimer, asesor tecnico, Causer SA, Alvear-SantaFe, Argentina; Amparo Botella, Ismael Quesada SA, Spain. Well done!

Question 3: Photo Call

Readers were asked to identify our mystery person from parts of the photo and the clues: 1869 (should have been 1896), 1930, 1935, 1937.

Answer: Apologies to readers for a typo that meant our first clue was incorrect. As David Mann pointed out Wallace Hume Carothers was born 1896 (not 1869), and in a stellar career played a lead role in the invention of polychloroprene in 1930, and nylon in 1935 before his death in tragic circumstances in 1937. As David commented: “Who knows what else he could have gone on to achieve?” Again, sorry for the misleading clue and well done to the following readers who came up with the correct answer anyway:  David Mann, manager rubber technology, SI Group, Béthune, France: John Bowen, consultant, Bromsgrove, UK; Marzio Bussola,  Parker Hannifin Manufacturing Srl,  Italy; Jon Cutler, materials development manager, Trelleborg Sealing Solutions, Tewkesbury, UK; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd,  Caldicot, Monmouthshire, UK; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong province, Thailand.

Question 2: Tricky equations

Solve the equation:

2+3=8,

3+7=27,

4+5=32,

5+8=60,

6+7=72,

7+8=??

Answer:  98 - add the 2 digits together, subtract 1 then multiply by the first digit. This week saw a large number of responses, well done to John Droogan, advanced polymers and composites,  MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Amparo Botella, Ismael Quesada SA, Spain; John Bowen, consultant, Bromsgrove, Worcestershire, UK; David Mann, manager rubber technology, SI Group, Béthune, France; Yuichi “Joe” Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; Michael Easton, sales and marketing director, Globus, Manchester, UK; Varun Sureka, no details given; Julien Coupechoux, product manager, dipro pneu, Bondoufle, France ; Juraj Vozár, Service department Konštrukta - TireTech, Slovak Republic; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Duncan Thomson, general manager, Wuxi Elbe Polymer Technology; Sergio Peimer, Causer S.A., Santa Fe, Argentina.

Question 1: Photo call

For our first ever picture-based teaser, readers are asked to identify the person shown, with more of the image and/or a clue added each day until Thursday. Again you can supply a different guess/answer each day.

Clues: Belfast, pneumatic

Answer: Never mind the likes of Usain Bolt, Brad Pitt or even Donald Trump, our rubber industry ‘celebrities’ seem to be equally well recognised – even those from the 1800s. And, it’s back to the drawing board for our judges, as quite a few readers identified the mystery person, John Boyd Dunlop, from the very first picture clue. Well done to: David Mann, manager rubber technology,  SI Group, Béthune, France; John Bowen,. consultant, Bromsgrove, UK; John Droogan, advanced polymers and composites,  MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Thierry Montcalm, R&D Chemist, Soucy Caoutchouc, Québec, Canada; Amparo Botella, Ismael Quesada SA, Spain; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; Martin Görgen, Abt. FTA-W, Goodyear Dunlop Tires Germany GmbH; Liz O’Donovan AAtyremaster, Dublin, Ireland;Stephen Fulton, R&D technology development manager, Umicore Specialty Materials Brugge NV, Brugge, Belgium; Suman Dhar, Asst. general  manager International Business Devpt, Rubamin Ltd, India and Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy

FEBRUARY 2017

Spare a thought for our judges, who this month had their toughest ever task: deciding which of three particularly strong players should get our coveted award. In the end, it was the not-quite-correct but inspired guess of 'Michelin' after day one of Question 2 that clinched this month's title.

David Mann our new Brainiac of the Month >>

Question 4: Another one-a-day

By popular demand, this week we ran another ‘connection’ question. Again, a clue was given every day up to Thursday and readers were invited to supply a different guess/answer each day. The four clues were: Mitsubishi, England football team, Adidas and the Institute of Materials, Minerals and Mining.

Answer. The connection was the number 3, which is a feature of, or appears in, the logos of each – Mitsubishi, 3 diamonds; England, 3 Lions; Adidas 3 stripes; and the IoM3. The good news is that we had a clear winner: John Droogan who answered as soon as the second clue was issued, followed shortly after by David Mann. Our judging panel admits that this teaser was a bit UK-centric, so extra well done to readers from around the world who had a go throughout the week. But on the roll of honour are: John Droogan, Advanced Polymers and Composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; David Mann, manager rubber technology,  SI Group, Béthune, France; John Bowen, consultant, Bromsgrove, Worcestershire, UK; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand.

Question 3: Title total teaser

If, with some letters changed from lower to upper case: Conti can total 56 and Tata 146, what can Kraton add up to?

Answer: The question was elementary but – and not or the first time in our series – had more than one solution: If CoNTi = 54 [Cobalt (27) + Nitrogen (7) + Titanium (22)] and TaTa = 146 [Tantallum (73) + Tantallum (73) = 146] then Kraton could add up to 136 [Krypton (36) + Astatine (85) + Oxygen (8) + Nitrogen (7)]… or 123 [K=19, Ra=88, T(Tritium)=1, O=8, N=7].

Extra well done to this week's very select group: David Mann, manager rubber technology, Béthune, France; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn,Amphur Pluakdaeng, Rayong Province, Thailand; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot,  Monmouthshire, UK.

Question 2: One a day

This week we used a different format: asking readers to identify the connection between four clues. A different clue appeared each day up to Thursday and readers were invited to provide a different guess/answer each day. The four clues were: Horace, Andre, 1898, Michelin.

Strictly speaking our winner is Thierry Montcalm, who was first to answer ‘Bibendum’ - after the third clue. However, another star performer was David Mann, who answered Michelin after the very first clue. He switched to the Michelin man after day 2 and then Bibendum, on day 4. So, well done to everyone who replied with either of these answers: Thierry Montcalm, R&D Chemist Soucy Caoutchouc, Québec, Canada; David Mann, manager rubber technology, SI Group, Béthune Cedex, France; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; John Bowen, consultant, Bromsgrove, UK; Ian. P. Jones, managing director, Continental Division, Contitech Power Transmission Group, ContiTech UK Ltd, Wigan, UK; Liz O’Donovan, AAtyremaster, Dublin, Ireland; Amparo Botella, Ismael Quesada SA, Spain. Stephen Fulton, R&D technology development manager, Umicore Specialty Materials Brugge NV, Brugge, Belgium. (Thanks to everyone who had a go: we saw a lot of great guesswork, ranging from various book and cartoon characters to ‘The Sound of Music’.)

Question 1: Credit cards?

Four playing cards, a 2, 3, 5 and 7 are placed face down on a table and mixed around.  To play you pay €10 and select two cards. You win €25 if the total on the two cards is nine. How much would you expect to win or lose if you played the game 16 times?

Answer: Things are rarely straightforward on the ERJ Brainteaser. The official answer is that you would lose €93.33 (€25 x (1/6) - €10) x 16). However, as some pointed out, it could be €66, if €25 was a ‘net win’. Anyway well done to: David Mann, manager rubber technology, SI Group, Béthune Cedex, France; John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; John Bowen, consultant, Bromsgrove, Worcestershire,UK; John D Burrows, consultant, France; Marzio Bussola, Parker Hannifin Manufacturing Srl, Italy; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; and Chris Kelley, director, global planning and asset optimization, Cabot Corp., Boston, Massachusetts, US.

JANUARY 2017

Competing at the highest levels is sometimes more about taking part rather than just winning all the time. Therefore, this month's award goes to a long-time supporter of our Brainteaser competition: well done the Liz O'Donovan of AA Tyremaster, the first ERJ Brainiac of the Month of 2017.

Question 4: Nerdy number

In the rubber QC lab, boffin Hamish is analysing a test sample labelled with a six-digit number. On closer inspection, he finds that when it is multiplied by either 2, 3, 4, 5 or 6 no new digits appear on the number on the label. What was the number?

Answer: The number is: 142857: Well done to John Bowen, consultant, Bromsgrove, Worcestershire,UK; Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand; John Droogan, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK. A couple of readers chipped in 000000 as an alternative answer, so well done also to; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; and Liz O’Donovan, AA Tyremaster Dublin, Ireland.

Question 3: Chocolate challenge

At a tire company cafeteria, the workers had a contest to see who could eat the most chocolate Santas left over from Christmas. After 20 minutes, all the Santas had been eaten. The foreman, who was keeping count, pointed out that there were seven times as many chocolates as workers and that each person had eaten a different number. And the shopfloor manager, who was acting as adjudicator, said she had noticed that when the workers had eaten one third of the Santas, there were 4 fewer than 10 times as many Santa ears as human noses in the contest.

Answer: Maybe a festive hangover, as there were only two correct replies to this fairly straightforward teaser: 42 Santas and 6 contestants. Well done to our top Brainiacs: Yuichi “Joe” Sano of Sumiden Steel Wire (Thailand) Co., Ltd in Thailand; and Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada.

Question 2: Paintball puzzle

Mr. Black, Mr. Gray, and Mr. White are having a paint-ball shoot-out. They each take turns shooting at each other with one hit taking a rival out of the game. Black, who hits target 1/3 of the time, gets to shoot first. Gray, who scores 2/3 of the time, gets to go next, assuming he is still in the game. White, who hits target every, shoots next, assuming also that he has not been hit. The cycle repeats. If you are Mr. Black, where should you shoot first for the highest chance of survival?

Answer: Based on the options presented, he should fire at Mr White, as worked out by: John Bowen, consultant, Bromsgrove, UK; Alexander Mamikonyan, chief of Export Dept, Empils-zinc Ltd, Russia; John Droogan, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; and  Yuichi "Joe" Sano of Sumiden Steel Wire (Thailand) Co., Ltd in Thailand.

The probabilities were neatly presented by Yuichi Sano as:

HIT(B->W)xMISS(G->B)+MISS(B->W)x(AIM(B)xMISS(G->B)+UNAIM)xUNAIM

1/3x1/3+2/3x(1/2x1/3+1/2)x1/2=1/3

HIT(B->G)xMISS(W->B)+MISS(B->G)x(AIM(B)xMISS(G->B)+UNAIM)xUNAIM

1/3x0+2/3x(1/2x1/3+1/2)x1/2=2/9

Question 1: Magic numbers

Find three magic number such that: The product of the three numbers is a prime; the 2nd number - 1st number = 3rd number - 2nd number.

Answer: Firstly Happy New Year to one and all and well done to the following readers who started 2017 on the right footing with the answer -3, -1, 1: John Droogan, MegaChem (UK), Caldicot, Monmouthshire, UK; Thierry Montcalm, R&D chemist, Soucy Caoutchouc, Québec, Canada; John Bowen, consultant, Bromsgrove, Worcestershire, UK; and Yuichi "Joe" Sano, Sumiden Steel Wire (Thailand) Co., Ltd, Tambol Mabyangporn, Amphur Pluakdaeng, Rayong Province, Thailand

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