Answer:
The correlation coefficient is A. -0.985.
Step-by-step explanation:
The correlation coefficient r measures the direction and strength of a linear relationship.
- It always has a value between -1, and 1.
- Strong positive linear relationships have values of r closer to 1.
- Strong negative linear relationships have values of r closer to -1.
- Weaker relationships have values of r closer to 0.
To find the r-value of the following data:
[tex]\left\begin{array}{c|ccccccc}X&5&7&10&15&19\\Y&19&17&16&12&7\end{array}\right[/tex]
Step 1: Find [tex]X\cdot Y[/tex], [tex]X\cdot X[/tex] and [tex]Y\cdot Y[/tex] as it was done in the table below.
Step 2: Find the sum of every column as it was done in the first image below.
Step 3: Use the following formula to work out the correlation coefficient as it was done in the second image below.
