Formulating a mean formula

In summary, the formula being used is ##\bar{x}_i = \frac14 \sum_{j=1}^{4}x_{ij}##, where ##\bar{x}_i## represents the mean of the four values in a set of data and ##x_{ij}## represents the jth value in the ith set of data. The goal is to calculate five mean values (x_1, x_2, x_3, x_4, x_5) by using this formula on five sets of data.
  • #1
random39a
7
0

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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  • #2
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.
 
  • #3
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?
 
  • #4
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}##
 

1. What is the purpose of formulating a mean formula?

The purpose of formulating a mean formula is to calculate an average value of a set of data points. This can help to summarize and understand large sets of data, and is commonly used in statistical analysis and research.

2. How is the mean formula calculated?

The mean formula is calculated by adding up all the values in a set of data and then dividing by the total number of values. For example, if we have the data points 5, 10, and 15, the mean can be calculated as (5+10+15)/3 = 10.

3. What are some common types of mean formulas?

Some common types of mean formulas include the arithmetic mean, which is the most commonly used method and is calculated by adding up all values and dividing by the total number of values; the geometric mean, which is calculated by taking the nth root of the product of n numbers; and the harmonic mean, which is calculated by dividing the number of values by the sum of their reciprocals.

4. Are there any limitations to using mean formulas?

Yes, there are some limitations to using mean formulas. One limitation is that it can be influenced by extreme values, also known as outliers, in the data set. Additionally, it may not accurately represent the data if the data is skewed or not normally distributed.

5. How are mean formulas used in scientific research?

Mean formulas are commonly used in scientific research to summarize and analyze large sets of data. It can help to provide a general understanding of the data and make comparisons between different groups or variables. Mean formulas are also used in inferential statistics to make predictions or draw conclusions about a larger population based on a sample of data.

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