Answer: 10%
Explanation:
(1 - 0.9) × 100 = 10%
With a correlation Coefficient of -0.9. This signifies a strong negative correlation between the x and y variables. That is an increase in the x variable leads to a corresponding decrease in the y variable and vice versa. The correlation Coefficient could also be interpreted to mean that about 90% of the variation in the y variable is explained by the regression line or equation. With the the remaining 10% being unexplained. This is why a correlation Coefficient of 1 or - 1 refers to a perfect relationship, meaning 100% variation in y is explained by the regression line.