ERJ Brainteaser: September

Question 3: Quite a tough one

Answer: When the going gets quite tough the, er, quite tough get going. Extra well done to elite players Kamila Staszewska, R&D / quality lead, Abcon Industrial Products Ltd, Cootehill, Co. Cavan, Ireland; Amparo Botella, responsable de Compras y Calidad, Ismael Quesada SA, Elche, Alicante, Spain; and everyone else who tried to tackle this toughie teaser.

SOLUTIONS

The official answer is: to get to 6,480 you multiply right hand column figures 24 by 15 (=360) and add left hand column figures 16 and 20. Then you multiply the two resulting totals (360 x 36) and divide the answer (12,960) by 2. Applying the same set of processes to the lower table gives you 7749.

Kamila Staszewska

if we take average of first column (16+20)/2=18 and multiply by the numbers in second column 18*24*15=6480

Analogously, (24+17)/2=20.5 ; 20.5*18*21=7749

Alternatively

Amparo Botella

 For the first square:

Diagonal products: 16x15=240 and 24x20=480.

Sum = 240+480=720.

Difference (top-right minus bottom-right) =24−15=9.

Result =720×9=6480

If we apply the same rule to the second square:

Diagonal products: 24x21=504 and 18x17=306.

Sum = 504+306=810

Difference (absolute number) 18−21=3.

Result =810×3=2430.

Belgium, E; Japan, Y; Sweden, K; South Korea, W; Thailand, B; UK, ?

Answer: The key here was to see that these were the first letters of the currencies in each country (see Solutions below). On the money this week were: Amparo Botella, responsable de Compras y Calidad, Ismael Quesada SA, Elche, Alicante, Spain; Andy Longdon, technical sales manager, Ceetak Ltd, Bedford UK; John Bowen, consultant, Bromsgrove, UK; John Coleman, membership manager, Circol ELT, Dublin, Ireland; Kamila Staszewska, R&D / quality lead, Abcon Industrial Products Ltd, Cootehill, Co. Cavan, Ireland; Sudi Sudarshan, principal consultant, Global Mobility Strategies, USA; Andrew Knox, Rubbond International, Ohé en Laak, The Netherlands; Peter D. Talbot, research scientist, Chem-Trend LP, Howell, MI, USA; Jose Padron, project manager, E2METRIX Canada Inc., Sherbrooke, Quebec, Canada. Well done to all and everyone else who had a go.

(NB: See also the solution below to very tricky Q1)

SOLUTIONS

Amparo Botella

I believe the missing letter is: P

As it seems that the letter that follows each country is the first letter of the country’s currency:

Belgium - Euro; Japan - Yen; Sweden - Krona; South Korea - Won; Thailand - Baht; UK - Pound.

Andy Longdon

List of official currencies:

Belgium, Euro; Japan, Yen; Sweden, Krona; South Korea, Won; Thailand, Baht; UK, PS (for Pound Sterling) (or perhaps just P(ound) or just S(terling))

John Bowen

Answer is : UK,  P

The letters are the initial of the country's currency:

Belgium = Euro, Sweden = Krona, S Korea = Won etc, so UK = Pound

John Coleman

These initials represent the unit of currency in each country, i.e.

E – Euro

Y – Yen

K – Krona

W – Won

B – Baht

Therefore, UK would be P for Pound Sterling.

Kamila Staszewska

These are the first letters of the country currency -the answer is UK, P (Pound).

Sudi Sudarshan

The answer to this week's Brainteaser is P.

The letters associated withbeach country is the first letter of the country's currency: Belgium - E(uro), Japan - Y(en), Dweden - K(rona), South Korea - W(on), Thailand - B(aht), U.K. - P(ound)

Andrew Knox

P for Pound Sterling

The letters correspond to the first letter of the currency of that country (Euro, Yen, Krone, Won (?) Baht, Pound).

Peter Talbot

The listed countries are represented by the first letter of their respective currencies:

Belgium, E(uro);

Japan, Y(en);

Sweden, K(rona);

South Korea, W(on);

Thailand, B(aht);

UK, P(ound)

Jose Padron

Hello, the list of countries and the associated letters are for their currency name, thus the answer is letter S according to the official name: Sterling.

However, the United Kingdom currency is also known as Pound Sterling or British Pound, so it could be a P, PS or BP as well.

Adding the code and currency sign for more information.

Question 1: Missing number

Answer: Extremely well done to Amparo Botella, responsable de Compras y Calidad, Ismael Quesada SA, Elche, Alicante, Spain – the only reader to work out that the missing number is 6.

SOLUTION

All the rows attend to this pattern: 10a−b−c−d+e=0

1st. raw: 10x2−4−10−13+7=0   then: 20-4-10-13+7=0

2nd raw: 10x6-22-19-20+1=0    then: 60-22-19-20+1=0

3rd raw: 10x3-13-?-20+9=0   then 30-13-?-20+9=0   so 17-20+9=? …. 6=?

4th raw: 10x4-13-17-18+8=0    then 40-13-17-18+8=0.

Or the official way of working this out:

In each row, the sum of the numbers in the centre three boxes is a two-digit number, comprised on the first digit in the outside left box and the second digit in the outside right box. So, 13 + 6 + 20 = 39 ie 3 on the outside left and 9 on the outside right.