# MATHEMATICS

16. In a small graduate math class with only five students, the professor gives a difficult, unannounced quiz. For the scores are lower than 30, but one students gets a 95. Which of the following is true?

A) The median and mean scores are the same.

B) It is impossible to tell whether the mean to the median is higher

C) The mean score is greater than the median score

D) The mean score is less than the median score

17.

Variable N Mean Minimum Q1 Median Q3 Maximum

Studying 451 13.6 0 7 10 18 70

Shown above is a summary of response to a Stat200 survey where students were asked how many hours they study each week. Use this to complete the following sentence: About 25% of the students said they study more than ___hours per week.

A) 10

B) 13.6

C) 7

D) 18

18. There are 16 students in a class. Every day the instructor randomly calls on five different students, and a student cannot be called on twice in the same class. Today the instructor has already called on four students, and Tony has not yet been called on. Given this information, what’s the probability that Tony will be the fifth student called?

A) 1/4

B) 1/2

C) 1/12

D) 1/16

19.

Variable N Mean Minimum Q1 Median Q3 Maximum

Studying 451 13.6 0 7 10 18 70

Shown above is a summary of responses to a Stat200 survey where students where asked how many hours they study each week. Which choice is an interval that gives the middle 50% of the weekly hours spent studying for these students?

A) 7 to 18

B) 0 to 10

C) 0 to 13.6

D) 10 to 70

20. You finally graduated from college and are interviewing for two jobs. You estimate the probability of receiving a job offer from Company A to be 0.4. The probability is 0.36 that both Company A and Company B will offer you a job. Given Company A offers you a job, what is the probability that Company B will also offer you a job?

A) 0.144

B) 1.11

C) 0.90

D) 0.36

21. The distribution of blood types among white Americans is approximately as follows: 37% type A, 13% type B, 44% type O, and 6% type AB. Suppose that the blood types of married couples are independent and that both the husband and wife follow this distribution. What is the probability that one person of a randomly chosen couple has type A blood and the other has type B?

A) 0.0484

B) 4.81

C) 0.0962

D) 0.2400

E) .05000

22.

Define the events R = {yes, date difference race} and S – {yes, approve same sex}. Are the events R and S independent?

A) The two events are dependent because P(R)*P(S) equals P(R and S)

B) The two events are dependent because P(R)*P(S) does not equal P(R and S)

C) The two events are independent because P(R)*P(S) does not equal P(R and S)

D) Need more information to tell if independent

E) The two events are independent because P(R)*P(S) equals P(R and S)