Windless surfing company’s marketing manager observes that if the price of designer windsocks is $45, then on average 75 windsocks are sold per month. experience has shown that if the price is raised from $45, then for every $1 increase in price, three fewer windsocks are sold each month. a. write an equation for the number of windsocks sold per month in terms of the price. b. what price results in zero windsocks per month being sold? c. if the manager wants to sell at least 60 windsocks each month, what range of possible prices for the windsocks must she set?

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?