b. What percentage of all possible observations of the variable are at most 12​?

Question

Assume that the variable under consideration has a density curve. The area under the density curve that lies to the right of

12

is

0.371.

a. What percentage of all possible observations of the variable exceed

12​?

b. What percentage of all possible observations of the variable are at most

12​?

Answer 1

Th area under a density curve should equal 1.

If the area to the right of 12 corresponds to .371 then it is safe to assume the percentage of all possible observations that exceed 12 is 37.1%

The percentage of all possible observations of the variable are at most

12​ can be found by subtracting .317 from the total area of the density curve, 1.

1-.317 = .683 which is the same as 68.3%

Hope this helps!