Why do you multiply by a power of 10 when writing a repeating decimal as a rational number

If f(x) = 2x + 2 and g(x) = x? , what is (gºf)(2)?

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?

Evaluate the function , when d = {9, 15, 30}. r = {5, 7, 12} r = {6, 10, 15} r = {6, 10, 20} r = {5, 12, 20}