-1, 0, 2, 3, 7, 10, 10
1. The mean, , of the data above is (to the nearest 1/10)
a. 8.3
b. 9.0
c. 9.4
d. answer not listed
2. The median of the data above is
a. 5.0
b. 7.1
c. 10.0
d. answer not listed
3. The mode of the data above is
a. 8.3
b. 10
c. 31
d. answer not listed
4. The standard deviation of the data above is (to the nearest 1/10)
a. 5.0
b. 5.3
c. 6.3
d. answer not listed
The table below shows the frequency distribution for 10 students on a test with a maximum score of 12. Use these sample data to answer questions 5 through 7:
5. The mean score, , of the data in the frequency distribution above is (to the nearest 1/10)
a. 5.0
b. 5.3
c. 5.4
d. Answer not listed
6. The standard deviation of the scores in the frequency distribution above is (to the nearest 1/10)
a. 1.8
b. 3.0
c. 3.2
d. Answer not listed
7. The median score lies in which score interval?
a. 1 - 3
b. 4 - 6
c. 7 - 9
d. 10 - 12
8. A delivery truck must make stops in eight different cities, designated by the first letter in the name of the city: A, B, C, D, E, F, G, and H. If the order in which the truck visits the eight locations is chosen randomly, what is the probability that it will visit them in alphabetical order?
9. A jar contains 12 marbles, 5 of which are blue and 7 of which are red. If 4 marbles are chosen at random and without replacement, what is the probability of selecting 3 blue ones and 1 red one?
11. If a student taking the course online is chosen at random, the probability that the person is male is
12. If a male is chosen at random, the probability that he is taking the course in the traditional mode is
13. The events of "choosing a male" and "taking a the course online" are
a. independent events;
b. dependent events;
c. mutually exclusive events;
d. none of the above
14. Acme Airlines flies airplanes that seat 12 passengers. From experience, they have learned that, on average, 80% of the passengers holding reservations for a particular flight actually show up for the flight. If they book 13 passengers for a flight, what is the probability that 12 or fewer passengers holding reservations will actually show up for the flight?
a. less than 90%
b. between 90 and 95%, inclusive
c. more than 95%
d. cannot be determined from information given
15. What is the minimum percentage of data in any frequency distribution that lies within 3 standard deviations of its mean?
a. 67%
b. 75%
c. 25%
d. Answer not listed.
16. Let be a normally distributed random variable with and the probability that is between 70 and 110 is (to the nearest whole percent)
a. 8 %
b. 84 %
c. 95%
d. answer not listed
17. If events A and B are complementary events, each with non-zero probability, then
a. and are mutually exclusive
b. A and B are independent
c. both (a) and (b)
d. neither (a) nor (b)
18. If A and B are independent events then
19. In selecting a sample from a population for the purpose of making an inference from the sample about the population, it is important
a. that the sample be chosen randomly
b. that the sample have a minimum size of n = 30
c. both (a) and (b)
d. neither (a) nor (b)
20. If a population is normal, then a distribution of sample means (of constant sample size n) from the population of will satisfy which of the following?
21.Let a random sample be taken of size from a population with known standard deviation of . Suppose that the mean of the sample is. The approximate 95% confidence interval for the mean, , of the population from which the sample was drawn
22. Among 100 people randomly chosen in a survey, exactly 10 stated that they believed that the elected representatives are honest most of the time. The approximate 99% confidence interval for the percentage of the population who believe that such people are honest most of the time is
23. Let a random variable representing the sum of trials. Then is a binomial random variable if all of the following are satisfied except
24. Each of the following is a measure of center except
25. A sample is necessarily random if
a. the sample is chosen without replacement from the population
b. the sample is chosen with replacement from the population
c. each member of the population had an equally likely chance of being chosen for the sample
d. none of the above