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What is the value of the correlation coefficient r of the data set? Please Help!!!?

Will give Brainliest answer :)
I am so lost
Options:

-1
-0.81
0.66
0.81

What is the value of the correlation coefficient r of the data set Please Help Will give Brainliest answer I am so lost Options 1 081 066 081 class=

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remotecontrolbrain

The formula for the correlation coefficient is quite messy. I suggest checking some websites discussing this and am also attaching the formula how to calculate it by hand (the ∑'s mean summation over all the elements listed.

But unless your teacher does not allow using online calculators, you can use them. I used python's function to process the data in the table and the result is approximately -0.81. So that's your answer.

Negative value like -0.81 means that the variables x and y are quite "anit-correlated" meaning the value behave like opposites: when x is small, y tends to be large, and vice versa.  

Ver imagen remotecontrolbrain

Answer:

-0.81

Step-by-step explanation:

x y xy

12 6 72

13 21 273

14 14 196

6 28 168

25 2 50

31 1 31

1 67 67

Total   857

   

Mean 14.57142857 19.85714286 214.25

Std dev 10.37396007 23.06099572  

   

Cov (x,y) -75.09693878  


Correlation coefficient is obtained by the formula

r = {E(xy)-E(x)E(y)}/(std dev x )(std dev y)

From the data we find x bar=14.57 and y bar = 19.86

STd dev of x = 10.37 and y = 23.06

E(xy) = average of product x and y = 214.25

Hence substitute to get r = -0.81


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