There were 81 runners to start a race. In the first half of the race, 1/3 of them dropped out. In the second half of the race, 2/3 of the remaining runners dropped out. How many runners finished the race?

As part of an annual fundraiser to raise money for diabetes research, diane joined a bikeathon. the track she biked on was 1,920 yards long. diane biked 38.5 laps. her sponsors agreed to donate an amount of money for each mile she biked. how many miles did she bike? first fill in the blanks on the left side using the ratios shown. then write your answer. given ratios: 5280ft / 1 mi , 1 mi /5280 ft , 1,920 yards / 1 lap , 1 lap / 1,920 yards , 3 ft / 1 yard , 1 yard / 3 ft. blanks: 38.5 laps / 1 yard x (blank) x (blank) x (blank) = (blank) miles i'm really confused on how to do this, and the explanations aren't exactly . if you could walk me through how to do this, it would be greatly appreciated.

State if the two triangles are congruent. if they are, state how you know?

Which shows the correct substitution of the values a, b and c from the equation 1=-2x+3x^2+1