In the race Math $600$, drivers must complete $200$ laps of $3$ miles each. Dave drove the first $150$ laps at $180$ mph and the last $50$ laps at $200$ mph. What was Dave's average speed for the race, in miles per hour? Express your answer as a common fraction.

Agraph of a trapezoid can have diagonals with slopes that are negative reciprocals and two pairs of adjacent sides that are congruent, true or false, and why

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?

Find an bif a = {3, 6, 9, 12) and b = {2, 4, 6, 8, 10).