Aregression model is used to forecast sales based on advertising dollars spent. the regression line is y=500+35x and the coefficient of determination is .90. which is the best statement about this forecasting model? a. for every $35 spent on advertising, sales increase by $1.
b. even if no money is spent on advertising, the company realizes $35 of sales.
c. the correlation between sales and advertising is positive.
d. the coefficient of correlation between sales and advertising is 0.81.

The correlation between sales and advertising is positive.

Step-by-step explanation:

For every $35 spent on advertising, sales increase by $1

Is FALSE, since y = 500 + 35 x $35, sales increase more than $1

Even if no money is spent on advertising, the company realizes $35 of sales

Is FALSE, if no money is spent, the sales amount to $ 500 (when X = 0)

The coefficient of correlation between sales and advertising is 0.81

Is FALSE, since R² = 0.9. The coefficient of correlation = R = 0.94, not 0.81

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: