Hillary can invest her family savings in two assets: riskless Treasury bills or a risky vacation home real estate project on an Arkansas river. The expected return on Treasury bills is 4 percent with a standard deviation of zero. The expected return on the real estate project is 30 percent with a standard deviation of 40 percent. Refer to Scenario 5.10. Hillary says that she always would like to take 1 percent higher stadnard deviation as long as the expected return also is 1 percent higher. Giving her preference, how she should invest her saving

bd = 9 cm

step-by-step explanation:

in a 30°-60°-90° triangle, the ratio of side lengths is 1 : √3 : 2. that is, the longest side (hypotenuse) is twice the length of the shortest side.

all of the triangles in your geometry are 30°-60°-90° triangles. ac is the hypotenuse of δacd, and the short side of δabc.

the short side ad of δacd will be half the length of ac, so 3 cm. the hypotenuse ab of δabc will be twice the length of ac, so 12 cm. segment bd is the difference of the lengths ab and ad, so is

bd = ab -ad

bd = 12 cm - 3 cm = 9 cm

comment on side length ratios

you can figure the ratios of side lengths in a 30°-60°-90° triangle by considering the trig ratios of the angles. or you can figure the length of the altitude of an equilateral triangle of side length 2 using the pythagorean theorem.