Shoppers at a local supermarket spend, on average, $85 during each shopping trip. Imagine the scatter-plot that shows the total amount spent each day in the store on the y-axis versus the number of shoppers each day on the x-axis.
(a) Would you expect a linear equation to describe these data?
(b) What would you expect for the intercept of the linear model?
(c) What would you expect for the slope?
(d) Do you expect patterns in the variation around the equation?