You’ve just performed a linear regression on the quantity of athletic shirts sold during sales targeting customers who have made New Year’s resolutions to get fit. If you have an intercept of 943 and a slope of -30, how many shirts would you estimate will be sold when the price is $12?

 
 
 
 
 
 

Using the formula US = a + b*Pi, you’ve correctly estimated that the number of shirts sold at $12 is 583.