1. The random variable X is normally distributed. The values 650 and 850 are at the 60th and 90th percentiles of the distribution of X, respectively.

 Quantity A Quantity B The value at the 75th percentile of the distribution of X 750

2. Eight hundred insects were weighed, and the resulting measurements, in milligrams, are summarized in the boxplot below. (a) What are the range, the three quartiles, and the interquartile range of the measurements?
(b) If the 80th percentile of the measurements is 130 milligrams, about how many measurements are between 126 milligrams and 130 milligrams?

3.  The company at which Mark is employed has 80 employees, each of whom has a different salary. Mark’s salary of $43,700 is the second-highest salary in the ﬁrst quartile of the 80 salaries. If the company were to hire 8 new employees at salaries that are less than the lowest of the 80 salaries, what would Mark’s salary be with respect to the quartiles of the 88 salaries at the company, assuming no other changes in the salaries?  (A) The fourth-highest salary in the ﬁrst quartile  (B) The highest salary in the ﬁrst quartile  (C) The second-lowest salary in the second quartile  (D) The third-lowest salary in the second quartile  (E) The ﬁfth-lowest salary in the second quartile 4. The median income of a group of College C graduates six months after graduation was$3,000 higher than the median income of a group of College D graduates six months after graduation.

 Quantity A Quantity B The 75th percentile of the incomes of the group of College C graduates six months after graduation The 75th percentile of the incomes of the group of College D graduates six months after graduation

5.  The 75th percentile on a test corresponded to a score of 700, while the 25th percentile corresponded to a score of 450.

 Quantity A Quantity B 800 A 95th percentile score

6.  Set S = {2, 5, 7, 11, 16, 24, 28, 50, 52, 101, 120, 130}
What is the average of the first quartile (“Q1”) and the third quartile (“Q3”) of set S?

(A) 9
(B) 26
(C) 42.75
(D) 76.5
(E) 85.5

7. The test scores at Millbrook High School are normally distributed, and the 60th percentile is equal to a score of 70.

 Quantity A Quantity B The 30th percentile score 35

8. Exam grades among the students in Ms. Harshman’s class are normally distributed, and the 50th percentile is equal to a score of 77.

 Quantity A Quantity B The number of students who scored less than 80 on the exam The number of students who scored greater than 74 on the exam

9.  The length of bolts made in factory Z is normally distributed, with a mean length of 0.1630 meters and a standard deviation of 0.0084 meters. The probability that a randomly selected bolt is between 0.1546 meters and 0.1756 meters long is between

(A) 54% and 61%
(B) 61% and 68%
(C) 68% and 75%
(D) 75% and 82%
(E) 82% and 89%

10. Jane scored in the 68th percentile on a test, and John scored in the 32nd percentile.

 Quantity A Quantity B The proportion of the class that received a score less than John’s score The proportion of the class that scored as high as or higher than Jane

11.  In a set of 10 million numbers, one percentile would represent what percent of the total number of terms?

(A) 1,000,000
(B) 100,000
(C) 10,000
(D) 100
(E) 1

12.  On a particular test whose scores are distributed normally, the 2nd percentile is 1720, while the 84th percentile is 1990. What score, rounded to the nearest 10, most closely corresponds to the 16th percentile?

(A) 1,750
(B) 1,770
(C) 1,790
(D) 1,810
(E) 1,830

13.  300 test results are integers ranging from 15 to 75, inclusive. Dominick’s result is clearly in the 80th percentile of those results, not the 79th or the 81st.

 Quantity A Quantity B Number of other test results in the same percentile as Dominick’s Maximum number of other test-takers with the same result as Dominick

14. The outcome of a standardized test is an integer between 151 and 200, inclusive. The percentiles of 400 test scores are calculated, and the scores are divided into corresponding percentile groups.

 Quantity A Quantity B Minimum number of integers between 151 and 200, inclusive, that include more than one percentile group Minimum number of percentile groups that correspond to a score of 200

1 B
2 (a) range=41, Q1 =114, Q2 =118, Q3 =126, interquartilerange=12  (b) 40 measurements
3 E
4 D
5 D
6 C
7 D
8 C
9 D
10 C
11 E
12 D
13 C
14 A