Arrel A cereal company finds that the number of people who will buy one of its products in the first month that it is introduced is linearly
related to the amount of money it spends on advertising. If it spends $60,000 on advertising, then 100,000 boxes of cereal will be
sold, and if it spends $70,000 on advertising, then 200,000 boxes of cereal will be sold.
(a) Write an equation that relates the amount A spent on advertising to the number of boxes the company aims to sell.
(b) How much advertising is needed to sell 300,000 boxes of cereal?
(c) Interpret the slope.

Data from 2005 for various age groups show that for each $100 increase in the median weekly income for whites, the median weekly income of blacks increases by $105. also, for workers of ages 25 to 54 the median weekly income for whites was $676 and for blacks was $527. (a) let w represent the median weekly income for whites and b the median weekly income for blacks, and write the equation of the line that gives b as a linear function of w. b = (b) when the median weekly income for whites is $760, what does the equation in (a) predict for the median weekly income for blacks?