Question 44616
Suppose that 6.5 million pounds of coffee are sold when the price is $8 per pound, 
and 4.0 million pounds are sold when it is $9 per pound. 
(4) a) Determine the ratio of the change in price of coffee to the change in the amount of coffee sold.

[6.5 mil - 4 mil]/[8-9)]= -1.5 mil 
(4) b) Determine the linear equation which models the amount of coffee sold, Y, and the price of coffee X.

6.5 mil = (-1.5 mil)8 + b
6.5 mil = -12 mill + b
b=18.5 mil
EQUATION:
amt of coffee sold in pounds  = -1.5 mil (cost per pound) + 18.5 mil pounds
Y = -1.5 mil (X) + 18.5 mil
Cheers,
Stan H.