Jean is trying to read her grocery receipt , but it is blurry . the sales tax rate was 7.75% . she pays tax only on the items labeled with a t .

how much sales tax did she pay ?

dog food $12.97 t, hand soap $3.39 t, peanut butter $2.99 f, past $1.12 f

sales tax =$

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?