On 27 January 2017, the sixth annual edition of the Dutch Mathematics Olympiad for Businesses was held at the Amsterdam Zuidas office premises of institutional trader Optiver. Altogether 72 participants divided over 24 teams took part in this competition. Statistics Netherlands (CBS) was represented by two teams competing for the honour. Both team leaders, Eugène van der Pijll and Igor Džambo, had already participated several times and Van der Pijll and his team are three-time winners of first prize. ‘Mathematics is fun! And very important to CBS.’

Frank has two whole numbers that, when added up, amount to 26. Kees adds another two whole numbers-and comes to a total of 41. Pieter adds another two whole numbers, resulting in a total of 58. At least how many of these six added numbers are even? You can choose from 0, 1, 2, 3 and 4.

This was the first challenge in the preliminary round of the 2016 Maths Olympiad for Students. Identical problems are presented to the contestants in the Mathematics Olympiad for Businesses. The latter is held for the sponsors of the student contest. Participants include not only employees of CBS but also of various banks, ICT companies, traders, universities and CITO Netherlands. CBS sends five among well over one hundred participants. It has been a sponsor of the Mathematics Olympiad for many years. After all, without mathematics there would not be a CBS. The young participants who join the competition fit well into CBS’ job profiles.

‘Taking a pragmatic approach is what we do here on a daily basis’

## Speed as a strength

The contestants were given twelve problems to solve. ‘These require, most importantly, logical thinking’, says Igor Džambo. ‘That, plus speed. We need to solve the same problems as the students but we have a lot less time. That is why we’ll always win if our colleague Eugène van der Pijll is on board, as he works really fast.’ The problems do not require any complex mathematical formulae. ‘The most difficult one is Pythagoras's theorem’, says Van der Pijll. In addition to the twelve problems, there is a bonus challenge which is taken from the student competition finals. ‘That one is really difficult and will make the difference.’

## Fun puzzles

Džambo already joined the Maths Olympiad once as a secondary school student. ‘My thinking was far too complicated then. There is no need for that, they are like fun puzzles; they’re about applying calculations to a practical situation.’ Naturally, this is also everyday practice at CBS. Van der Pijll agrees: ‘Taking a pragmatic approach is what we do here on a daily basis.’ The Mathematics Olympiad has prizes for best business and for best individual contestant. CBS previously won first prize in three of the competitions, but this time, the top honour went to employees of Booking.com. About the challenge mentioned earlier, what was the answer? Dzambo: ‘The right answer is 2.’