For which data set is a linear regression most reasonable?
a set of nine data pairs with a correlation coefficient r = –0.4
a set of five data pairs with a correlation coefficient r = 0.3
a set of four data pairs with a correlation coefficient r = –0.8
a set of six data pairs with a correlation coefficient r = 0.6

a set of four data pairs with a correlation coefficient r = –0.8

Step-by-step explanation:

We know that the correlation tells the strength of a relationship between two variables where a strong correlation means that two or more variables have a strong reasonable relationship with each other.

For strong correlation, the value of correlation coefficient must be nearest to the absolute value of 1.

Here the nearest value of correlation coefficient is -0.8 , which is nearest to -1, Hence there is strong negative correlation among all.

Therefore,a set of four data pairs with a correlation coefficient r = –0.8 is where the linear regression model is reasonable.

11

step-by-step explanation:

32.50-7.50=25

225/25=11

step-by-step explanation: