How Can I Mathematically Represent Five Mean Values in a Formula?

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Homework Statement



I'm trying to formulate a formula based on an experiment I did.

Homework Equations



The Attempt at a Solution



jOQRNgZ.jpg
[/B]

where

x_1 = mean (one of 5 mean values)
x_i = value of variables (there are 4 of them added together)
n = number of variables

My problem is, for the left hand side of the formula, I want to show that there are 5 means, so x_1 to x_5 = the right hand side as shown

I'm not sure how to show this mathematically.

Wonder if anyone might be able to help.

Thanks.
 
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random39a said:

Homework Statement



I'm trying to formulate a formula based on an experiment I did.

Homework Equations



The Attempt at a Solution



jOQRNgZ.jpg
[/B]

where

x_1 = mean (one of 5 mean values)
x_i = value of variables (there are 4 of them added together)
n = number of variables
I don't understand what you're doing.
##x_1## is one of the four values in your summation. ##\bar{x_1}## is the mean of the four values. Since your summation runs from 1 to 4, I assume you mean for n to be 4, not 5 as you seem to indicate.
With n = 4, we have ##\bar{x_1} = (1/4)(x_1 + x_2 + x_3 + x_4)##
random39a said:
My problem is, for the left hand side of the formula, I want to show that there are 5 means, so x_1 to x_5 = the right hand side as shown
?
For the four numbers you're adding, there is only one mean.
 
Mark44 said:
I don't understand what you're doing.
##x_1## is one of the four values in your summation. ##\bar{x_1}## is the mean of the four values. Since your summation runs from 1 to 4, I assume you mean for n to be 4, not 5 as you seem to indicate.
With n = 4, we have ##\bar{x_1} = (1/4)(x_1 + x_2 + x_3 + x_4)##
?
For the four numbers you're adding, there is only one mean.
Thanks for reply.

I'm just trying to let the person who reads the formula know that I have used this formula to calculate 5 mean values x_1, x_2, x_3, x_4 and x_5.

eg/

result number one x_1 of 5 results x_5

YELLOW

499

ORANGE

317

PURPLE

545

BLACK

110

AVERAGE

367.75

The data above is one of 5 sets of data for which I have to calculate the mean.

For this data, I calculated the mean using my formula x_1= 1/4 (Sum of Yellow, Orange, Purple, Black) = 367.5

I did this 4 more times with 4 other data sets just like this one.

Does this make sense what I'm trying to do?
 
random39a said:
Thanks for reply.

I'm just trying to let the person who reads the formula know that I have used this formula to calculate 5 mean values x_1, x_2, x_3, x_4 and x_5.

eg/

result number one x_1 of 5 results x_5

YELLOW

499

ORANGE

317

PURPLE

545

BLACK

110

AVERAGE

367.75

The data above is one of 5 sets of data for which I have to calculate the mean.

For this data, I calculated the mean using my formula x_1= 1/4 (Sum of Yellow, Orange, Purple, Black) = 367.5

I did this 4 more times with 4 other data sets just like this one.

Does this make sense what I'm trying to do?
You need something like:
##\bar{x}_i = \frac14 \sum_{j=1}^{4}x_{ij}##

Where ##\bar{x}_i## is the average of the ##i##th set of data ##x_{i1} \dots x_{i4}##