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A sign of the times brainteaser

By , 7 August 2019

Terri was doing sums for her signwriting business. She worked out that one-third of six and two-thirds of eleven together made seven. Her maths might seem wonky, but she was completely correct. Can you work out what she was trying to do?

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Brainteaser answer

Terri was looking at the letters in the words six, eleven and seven so she could make a sign. She realised you could take one-third of the letters in (s)ix and two-thirds of the letters in el(even) and make (s)(even)!

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  1. it also works if she is doing it in base 8!

    1. almost! but 11 (base 8) = (9 base 10) so
      1/3 of 6 + 2/3 of 9
      = 2 + 6
      = 8

      To get the numbers to work out I think you need to work in base 6.5


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