Question

What is the r-value of the following data, to three decimal places

Answer 1

Answer: A. -0.903

Step-by-step explanation: I just did this on A P E X and got it right

Answer 2

Option: A is the correct answer.

A. -0.903

Explanation:

The formula to calculate correlation coefficient r is given by:

`r=(n\sum xy-(\sum x)(\sum y))/(√(n(\sum x^2)-(\sum x)^2)√(n(\sum y^2)-(\sum y)^2))`

x y xy x² y²

4 23 92 16 529

5 12 60 25 144

8 10 80 64 100

9 9 81 81 81

13 2 26 169 4

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∑ 39 56 339 355 858

Also n=5 ( as there are 5 data points )

Hence, we get:

`r=(5* 339-39* 56)/(√(5* 355-(39)^2)* √(5* 858-(56)^2))\\\\\\r=(-489)/(√(254)* √(1154))\\`

`r=-(489)/(541.40188)=-0.9032`

Hence, the r-value of the following data, to three decimal places is:

A. -0.932