Charles wants to find out if the students in foreign language classes spend more time in class speaking in english or in the foreign language they are studying. charles first gets class lists of all students taking foreign language classes. he then chooses 10 students from each different language class to survey. which best explains why the sample he chose may not be a representative sample?

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?