For women at Hartford College, times to run 400 meters are normally distributed with a mean of 84 seconds and a standard deviation of 6 seconds. What percentage of the times are more than 72 seconds?

Let n = one of the angles
Let 2n -30 = the other

n+ 2n -30 =90⁰  (because they are complementary)
Combine like terms --     3n -30 = 90
Add 30 to both sides of the equation
3n=120°
 Divide both sides by 3 and n=40°    2n -30 = 80 -30 = 50°
So one angle is 40° and the other is 50° and those angles are complementary.