ERJ Brainteaser - November

Question 1: Sequence-wise

35.6, 37.4, 41.0, 44.6,  ?  ,

Clues: Getting warmer?, prime time... 

Answer: Well done, in order of reply, to this week’s prime movers: Andrew Knox, Rubbond International, Ohé en Laak, The Netherlands; John Coleman, membership manager, Circol ELT, Dublin, Ireland; Sudi Sudarshan, principal consultant, Global Mobility Strategies, USA; 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; Eur Ing John Bowen BSc [Hons], CEng, MIMMM, consultant, Bromsgrove, UK; Hans-Bernd Luechtefeld, consultant, Germany; Peter D. Talbot, research scientist, Chem-Trend LP, Howell, MI, USA; and everyone else who had a go. 

SOLUTIONS

Andrew Knox

Answer: 51.8

Sequence is ascending prime numbers (2, 3, 5, 7, 11) as values in degC, converted into degrees Fahrenheit. So, 11 x 9/5 = 51.8.

John Coleman

Question 1: Sequence-wise

35.6, 37.4, 41.0, 44.6,  ?  ,   

These are the Fahrenheit equivalent temperatures of the first four prime numbers in centigrade, i.e.

Therefore, the next number in the sequence is 51.8 which is the Fahrenheit equivalent of 11°C.

Sudi Sudarshan

The numbers, if regarded as temperature readings in Fahrenheit,  when translated to Celsius are:

(35.6 - 32)*5/9 = 2

(37.4 - 43)*5/9 = 3...

We get the sequence

2, 3, 5, 7, ...

This is the sequence of prime numbers. The next prime number is 11.

11°C  translates to 11*9/5 + 32 = 51.8°F 

Kamila Staszewska

These are temperatures in Fahrenheit that corresponds with "prime" degrees in Celsius:

35.6(°F) = 2(°C)

37.4(°F) = 3(°C)

41.0(°F) = 5(°C)

44.6(°F) = 7(°C)

Next in the sequence is 11(°C) which is 51.8 (°F).

Amparo Botella

Very complicated this time, but the clue, seems to have clarify something.

I believe the numbers given are Fahrenheit grades that correspond to prime-number Celsius grades:

Following the conversion formula: ºC=(ºF-32)/1.8

35.6°F → (35.6−32) ÷ 1.8 = 3.6 ÷ 1.8 = 2°C

37.4°F → (37.4−32) ÷ 1.8 = 5.4 ÷ 1.8 = 3°C

41.0°F → (41.0−32) ÷ 1.8 = 9.0 ÷ 1.8 = 5°C

44.6°F → (44.6−32) ÷ 1.8 = 12.6 ÷ 1.8 = 7°C

Next prime after 7 is 11°C. Convert 11°C to °F:

ºF=(ºCx1.8)+32

ºF=(11x1.8)+32=19.8+32=51.8

So the missing term is 51.8.

John Bowen

The numbers given are the Farenheit values of  2,3,5,7 Celsius

Next would be 9C or 48.2 in Farenheit

Hans-Bernd Luechtefeld

We are looking for the next prime number in Fahrenheit: 51.8

Sequence:

35.6 F = 2°C, 37.4 F = 3°C, 41 F = 5°C, 44.6 F = 7°C => 51.8 F = 11°C

Peter Talbot

This series comprises temperatures expressed in °F derived from a series of values originated in °C.

On examination, 35.6°F = 2°C, 37.4°F = 3°C, 41.0°F = 5°C , 44.6°F = 7°C.

2,3,5 & 7 are the first 4 prime numbers. The next and 5th member of this series is 11.

Therefore, the value we are looking for in this brainteaser is 11°C expressed in °F = 51.8.

News teaser on Monday.