This is quite extraordinary.
Two modern calculators.
Both made by the same manufacturer, Casio.
Type 6÷2(1+2)= into one and the response is 1, but on the other, it’s 9.
Mathematics abhors a contradiction; they cannot both be right.
Yet when I asked some A-level mathematics pupils which was correct,
they quickly polarised into two equal groups,
each arguing passionately for one of the two suggested answers.
read on: http://www.mathmagical.co.uk/Mathematics/CalcPuz.html
Thanks Colin!




