为什么这里不用考虑残差项?

问题如下：

If the ratio of net income to sales for a restaurant is 5%, the predicted ratio of cash flow from operations (CFO) to sales is closest to:

选项：

A.-4.054 B.0.524. C.4.207

解释：

C is correct. To make a prediction using the regression model, multiply the slope coefficient by the forecast of the independent variable and add the result to the intercept. Expected value of CFO to sales = 0.077 + (0.826 x 5) =4.207.