MHB Find Mean With Multiple Data [Shortcut]

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To find the mean with multiple data points, the formula used is \(\overline{x}=\frac{\sum\limits_{k=1}^n\left(x_kf_k\right)}{\sum\limits_{k=1}^n\left(f_k\right)}\). Users expressed confusion about applying this formula to their data samples. An Excel shortcut for this calculation is =SUMPRODUCT(A2:A5, B2:B5) / SUM(B2:B5). However, it was clarified that calculating the mean without multiplying each data point by its frequency is not feasible. The provided formulas represent the simplest method for computing the mean from a frequency table.
susanto3311
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hello everybody...

how to easy find mean with multiple data with simple formula [shortcut formula]?

please, see my picture..

thanks in advance...

susanto3311
 

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Here is the formula:

$$\overline{x}=\frac{\sum\limits_{k=1}^n\left(x_kf_k\right)}{\sum\limits_{k=1}^n\left(f_k\right)}$$

But to compute the mean using the above formula, you will have to essentially do what is shown in the table.
 
hi Mark, thanks but i confuse how to use your formula...

could you use my data sample (post #1)?
 
susanto3311 said:
hi Mark, thanks but i confuse how to use your formula...

could you use my data sample (post #1)?

Hi susanto3311! Welcome to MHB! :)

The formula for your mean is:
$$Mean = \frac{
\overbrace{35+35+...+35}^{6}
+ \overbrace{40+40+...+40}^{8}
+ \overbrace{25+25+...+25}^{12}
+ \overbrace{20+20+...+20}^{24}
}{6+8+12+24}$$

In your picture each of the sums under an overbrace has been put in a separate cell. The result is calculated afterwards.

In Excel, you can do it in one formula: [m]=SUMPRODUCT(A2:A5, B2:B5) / SUM(B2:B5)[/m].
This is the same formula as the one that Mark gave, just in Excel style. (Wasntme)
 
I like Serena said:
Hi susanto3311! Welcome to MHB! :)

The formula for your mean is:
$$Mean = \frac{
\overbrace{35+35+...+35}^{6}
+ \overbrace{40+40+...+40}^{8}
+ \overbrace{25+25+...+25}^{12}
+ \overbrace{20+20+...+20}^{24}
}{6+8+12+24}$$

In your picture each of the sums under an overbrace has been put in a separate cell. The result is calculated afterwards.

In Excel, you can do it in one formula: [m]=SUMPRODUCT(A2:A5, B2:B5) / SUM(B2:B5))[/m].
This is the same formula as the one that Mark gave, just in Excel style. (Wasntme)

i just want, how to find & calculate mean without hard work...
like my picture attach, without multiplication for each data with frequency...
do you have ideas?
 

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susanto3311 said:
without multiplication for each data with frequency...

Sorry, but that is not possible. (Dull)
The formulas given are the simplest way to calculate the mean of a frequency table.
 
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