ERJ Brainteaser: April 2019
25 Sep 2019
There can be absolutely no dispute about our top performer in April. For showing up first on the grid each time and navigating a tricky set of teasers, particularly Question 4, big congratulations go to:
John Droogan of MegaChem (UK) Ltd, our new Brainiac of the Month
Fill in the gaps in the following sequence?
_, 4, _; _ 8, 9, 10, _ ; _, 14, 15, 16, _ ; _, _, _, _, _.
Answer: The series comprises sets of numbers flanked by prime numbers in ascending order – though some readers got there using a different rationale.
3, 4, 5 7, 8, 9, 10, 11 13, 14, 15, 16, 17 19, 20, 21, 22, 23
We do try to keep our questions as original and as Google-proof as possible. As a result, solutions are sometimes a bit less straightforward than intended – as was the case this week.
However, detecting our ‘prime sandwiches’ straight away was John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK. His reply early Tuesday (day 1) was followed a little bit later by Franz Hochwimmer, sales & support inspection systems, Micro-Epsilon Messtechnik GmbH & Co. KG, Ortenburg, Germany; Paul Knutson, textile engineer, Timken Belts, Springfield, Missouri, USA; Thierry Montcalm, R&D and innovation manager, Soucy Techno, Canada; Jose Padron, material development specialist, Waterville TG Inc., Waterville, Québec, Canada; Ramasubramanian P, manager, marketing – mixer and LTKMPL products, Larsen & Toubro Ltd, Kanchipuram, Tamil Nadu, India; Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami, Japan. Well done to all, and everyone else who had a go.
A father, mother and their two children are crossing a river. Their boat can only take one adult or two children at a time. What is the minimum number of journeys needed to take the family of four across the river?
Answer: As per the first correct reply in from John Droogan, (see also table below from Jose Padron) it took them 9 journeys.
2 children across > 1 child back > 1 adult across > 1 child back > 2 children across > 1 child back > 1 adult across > 1 child back > (and finally) 2 children across.
Well done to: John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Hans-Bernd Lüchtefeld, market research & communication manager, PHP Fibers GmbH, Obernburg, Germany; David Mann, Polymer Business Development, France; Andrew Knox, Rubbond International, Ohé en Laak, The Netherlands; Bharat B Sharma, Sr VP Product Development & Technical Service (Elastomers), Reliance Industries Ltd, Vadodara, Gujarat, India; Michele Girardi, Scame Mastaf Spa, Suisio, Italy; John Bowen, consultant, Bromsgrove, UK; Jose Padron, spécialiste en développement de materiaux, Waterville TG Inc., Québec, Canada; Paul Knutson, textile engineer, Timken Belts, Springfield, Missouri, USA; Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami, Japan; Thierry Montcalm, R&D and innovation manager, Soucy Techno, Canada; Bob Hall, senior director global marketing, Kraton Polymers LLC, Houston, Texas, USA.
Complete the following series
8,485, 8,516, 8,586, 8,611, _.
Answer: Apologies to those readers who spent time trying to work this one out as a mathematical series. There was, though, a strong clue in the title, as the figures represent the height above sea level of the world’s five highest mountains. Our answer, so, was 8848m for Mount Everest, known as Sagarmatha in Nepal and Chomolungma in Tibet.
Well done to peak performers: John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Hans-Bernd Lüchtefeld, market research & communication manager, PHP Fibers GmbH, Obernburg, Germany (thanks for the photo); David Mann, Polymer Business Development, France; Lars Linnemann, R&D manager, Genan A/S, Viborg, Denmark; Bharat B Sharma, Sr VP Product Development & Technical Service (Elastomers), Reliance Industries Ltd, Vadodara, Gujarat, India (thanks for the table); Jose Padron, material development specialist, Waterville TG Inc., Waterville, Québec, Canada; Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami, Japan; Paul Knutson, textile engineer, Timken Belts, Springfield, Missouri, USA; John Bowen, consultant, Bromsgrove, UK.
What number comes next in this series?
100, 500, 1, 50, 1000, 5, ???
Answer: The series derives from Roman numerals placed in alphabetical order:
C (100), D (500), I (1), L (50), M (1000), V (5) and then our answer X (10).
Congratulations maximus go to: John Droogan, advanced polymers and composites, MegaChem (UK) Ltd, Caldicot, Monmouthshire, UK; Hans-Bernd Lüchtefeld, market research & communication manager, PHP Fibers GmbH, Obernburg, Germany; Amparo Botella, Ismael Quesada SA, Spain; John Bowen, consultant, Bromsgrove, UK; David Mann, Polymer Business Development, France; Bharat B Sharma, Sr VP Product Development & Technical Service (Elastomers), Reliance Industries Ltd, Vadodara, Gujarat, India; Yuichi (Joe) Sano, Sumitomo Electric Industries Ltd, Itami, Japan; Paul Knutson, textile engineer, Timken Belts, Springfield, Missouri, USA.
