Question

In 2003, the average combined SAT score (math and verbal) for college-bound students in the United States was 1026. Suppose that approximately 45% of all high school graduates took this test and that 100 high school graduates are randomly selected from among all high school grads in the United States. Which of the following random variables has a distribution that can be approximated by a binomial distribution? Whenever possible, give the values for n and p.
a. The number of students who took the SAT
b. The scores of the 100 students in the sample
c. The number of students in the sample who scored above average on the SAT
d. The amount of time required by each student to complete the SAT
e. The number of female high school grads in the sample

Answer 1

Answer:

The random variables which has a distribution that can be approximated by a binomial distribution is:

c. The number of students in the sample who scored above average on the SAT.

Step-by-step explanation:

The binomial distribution in this scenario will be between the number of students in the sample who scored below average on the SAT and the number of students who scored above average.  Variables that have a binomial distribution must meet these four conditions:

1: The observed number of students who sat for the SAT 'n' is not variable.  

2: Each student's score (observation) is purely independent of each other, either above or below average scores.  

3: Each student's score (observation) shows one of the two outcomes ("success" or "failure").  Those below average are "failures."  Those above average are "successes."

4: The outcome probability of "success" 'p' for each student is the same.