[Math] The difference between a / and ÷ use

notation

I'm confused with the $/$ symbol meaning the same as $÷$

$4+2(8-3)÷2-1$ should equal $8$ using PEMDAS.

However if using the Wikipedia's definition of the slash "Used between numbers slash means division, and in this sense the symbol may be read aloud as "over". For sets, it usually means modulo (quotient group). Proper typography requires a more horizontal line and the numbers rendered using superscript and subscript, e.g. $“123⁄456”$.

Using that definis equation could also be written as:

$\frac{4+2(8-3)}{2-1}$

To me the equation is now different and equals 14 by solving the top then solving the bottom then dividing the top by the bottom.

Can you shed light on this?

Best Answer

What you've written, using the horizontal line, is the expression:

$[4 + 2(8 - 3)]/(2-1)$, which is not the original expression. Using the "slash", or horizontal line, we have:

$$4 + \color{blue}{\bf 2(8-3)\div 2} - 1 = 4+\color{blue}{\bf 2(8-3)/2}-1 = 4 + \color{blue}{\bf \frac{2(8-3)}{2}} - 1.$$

In each case in the equality above, the scope of the division by $2$ is restricted to the dividend $2(8 - 3)$.

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