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Hi im suppost to write the expression

(w+x - y)/(pi * z^3) in Polish notation.

My answer was / - + w x y * pi ^ z 3

But the solution is / + w - x y * pi ^ z 3

Is my answer the same as the solution and if not what am I doing wrong?

Erika
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You've translated the potentially ambiguous formula $w + x - y$ that appears as the numerator of the fraction as if it read $(w + x) - y$, the other solution has taken it as $w + (x - y)$. The two readings are algebraically equivalent, but I think your reading agrees with the BODMAS rules (by working left to right given a sequence of additions and subtractions) - so I would challenge the other solution if I were you. (Note that if it were $w - x + y$, then reading it as $w - (x + y)$ rather than $(w - x) + y$ is definitely wrong.)

Rob Arthan
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  • I don´t understand why I need to calculate the order w+(x-y) first. Can you explain more? – Erika Dec 01 '20 at 13:10
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    The Polish notation is completely explicit about the order that the operations are applied. $w + x - y$ is potentially ambiguous. I believe that you have resolved the ambiguity correctly according to the usual rules for this (see BODMAS). I.e., I think the solution you have been given is wrong. – Rob Arthan Dec 01 '20 at 13:15