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I wish to display to people that a number is a total. I have decided to use the greek symbol for sum:

Σ

Do I prefix or suffix numbers with this symbol?

Given the total is 10.

Σ10

or

10Σ
  • 10
    If you really want to use $\Sigma$ for this, maybe $\Sigma=10$.2012-05-14
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    Indeed, a mathematician would interpret $\Sigma10$ as adding up some number of tens, and $10\Sigma$ as ten times some sum.2012-05-14
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    $\Sigma$ is generally used as an operator. Thus you might write $\sum_{i=1}^{3} a_i = 10$, which means that the sum of $a_i$ for $i$ from $1$ to $3$, i.e. $a_1 + a_2 + a_3$, is $10$.2012-05-14
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    THank you all. I would accept @Andre's comment if it were an answer.2012-05-15

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If $S_n$ is some sequence (for $n=a, a+1, a+2, \cdots, b-1, b$), its sum (total), $T$, is: $$T=\sum_{n=a}^b S_n$$

which is simply another way of saying

$$T=S_a+S_{a+1}+\cdots + S_{b-1}+S_{b}$$


Note also that $$C \sum_{n=a}^b S_n=C(S_a+S_{a+1}+\cdots + S_{b-1}+S_{b})$$

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    $S_n$ is a *sequence*; $T$ is (the value of) a *series*.2012-05-15