If a woman of 25 years of age or over were chosen at random from the entire U.S. population, here are the probabilities for her highest level of educational attainment:

To make this a legitimate assignment of probabilities, the probability that the woman chosen has less than a high school diploma as her highest level of educational attainment must be:
A)1)
B) 0.8.
C) 0.12.
D) -0.12.
E) 0.

Question

If a woman of 25 years of age or over were chosen at random from the entire U.S. population, here are the probabilities for her highest level of educational attainment:

To make this a legitimate assignment of probabilities, the probability that the woman chosen has less than a high school diploma as her highest level of educational attainment must be:
A)1) 
B) 0.8. 
C) 0.12. 
D) -0.12. 
E) 0.

Quizplus · Accepted Answer

To make this a legitimate assignment of probabilities, the sum of the probabilities for each possible outcome must equal 1. Therefore, the probability that a woman chosen has less than a high school diploma can be found by subtracting the sum of the probabilities for the other educational levels from 1:
P(Less than high school diploma) = 1 - (0.11 + 0.18 + 0.36 + 0.18 + 0.17) = 0. (Notice how we add up 0.11 to 0.17(degree) always even though options are marked for degree or above to make sure the sum remains 1)

Since this represents the probability for a possible outcome, it must be non-negative (i.e. greater than or equal to 0). Therefore, the correct choice is C) 0.12, which represents the probability that the woman chosen has a high school diploma or less as her highest level of educational attainment.

If a Woman of 25 Years of Age or Over