When calculators get it very wrong! Can you explain this?

When calculators get it terribly wrong! Can you explain this?

This is definitely an example of when calculators get it very wrong and would make a great starter for discussion and debate in any Maths lesson. It appears that one of the calculators has not been taught the order of operations, can you tell which one? : )

calculators get it wrong


Can you explain why this is the case? The original tweet caused a twitter storm and generated some interesting discussions. Comments are free, please leave one below.

calculators revealed

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  1. Andrew says:


  2. Miss Davies says:

    One worked left to right, the other has done the division last.

  3. Angela Little says:

    The 2nd is using BODMAS (or Order of Operations) which should be used. The first is just going from left to right.

  4. Frank Boulton says:

    The second uses the BODMAS rule, which is what I was taught at school. This is the correct way. The first seems to work from left to right. However, I wonder if the difficulty might lie in the fact that the expression has an implied but unwritten multiplication sign before the left parenthesis. I wonder what would happen with the first calculator, if we explicitly entered that multiplication sign.

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