Question

Data were collected on monthly sales revenues​ (in $1000s) and monthly advertising expenditures​ ($100s) for a sample of drug stores. the regression line relating revenues​ (y) to advertising expenditure​ (x) is estimated to be modifyingabove y with caret equals negative 48.3 plus 9.00 xy=−48.3+9.00x. what is the interpretation of the​ slope?

Answer 1

Interpretation:  For every $100 additional spent on advertising, the monthly sales revenue drops by $48.30.   Personally I'd expect that the sales revenue increases with every $100 spent on ads. 

Answer 2

The interpretation of the slope is that for each $1000 you spend, your revenue increases by $900.

Explanation:

We have that:

The revenue y is a function of the advertising expediture x, and the relationship is given by the following function:

y = -48.3 + 9x.

However, since y is in thousands and x in hundreds, i am going to rewrite

y = -48.3 + 0.9x

This means that if you spend no money in advertising, you lose -48.3 thousands of dollars. However, for each $1000 you spend, your revenue increases by $900.

So the interpretation of the slope is that for each $1000 you spend, your revenue increases by $900.