9231 P21 - Jun 2018 - Q11O - 12 marks
6187
Question 11 OR alternative.
The regression line of \(y\) on \(x\), obtained from a random sample of 6 pairs of values of \(x\) and \(y\), has equation
\[ y=0.25x+k, \]
where \(k\) is a constant. The values from the sample are shown in the following table.
| \(x\) | 4 | 5 | 7 | 8 | 10 | 14 |
|---|---|---|---|---|---|---|
| \(y\) | 5 | 8 | \(p\) | 7 | \(p\) | 9 |
(i) Find the value of \(p\) and the value of \(k\).
(ii) Find the product moment correlation coefficient for the data.
(iii) Test, at the \(5\%\) significance level, whether there is evidence of positive correlation between the variables.
Solutions locked. Please sign in with access to view them.