One of the rules in a public speaking contest requires contestants to speak for as close to 5 minutes (300 seconds) as possible. Contestants lose 3 points for each second they speak either
over or under 5 minutes. Which expression below can be used to determine the number of
points a contestant loses if she speaks for a seconds?

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?