- The relationship between two variables \(p\) and \(t\) is modelled by the regression line with equation
$$p = 22 - 1.1 t$$
The model is based on observations of the independent variable, \(t\), between 1 and 10
- Describe the correlation between \(p\) and \(t\) implied by this model.
Given that \(p\) is measured in centimetres and \(t\) is measured in days,
- state the units of the gradient of the regression line.
Using the model,
- calculate the change in \(p\) over a 3-day period.
Tisam uses this model to estimate the value of \(p\) when \(t = 19\)
- Comment, giving a reason, on the reliability of this estimate.