Download White Exam 1

STAT 3321 - Exam 1- White, Summer 2009
1. The angle of a pie slice in a pie chart is proportionate to
a. percent of values in a category
b. the frequency of the numbers in the numeric intervals
c. the color of the pie
d. a random sample
2. Ogives are used with
a. pie charts
b. quantitative data
c. qualitative data
d. relationships between two qualitative variables.
3. Two types of errors can occur. They are
a. variability and knowledge..
b. sampling and ultra-high, very important, stupendous beige-yellow sampling errors
c. sampling and non-sampling errors
d. ogives and histograms
4. A typical error in a sample mean consists of
a. nothing really important (Hint: BAD, BAD CHOICE)
b. variability and knowledge
c. a random sample
d. means and variance
5. When you read a problem that states that a distribution is mound-shaped symmetric you should…
a. all of the others are needed.
b. draw a judgment sample.
c. calculate the proportion of values using the binomial formula.
d. draw the empirical rule
6. The strength and weakness of the range as a measure of variability is
a. it uses all the data in the data set making it difficult to compute.
b. it can only be used with judgment samples
c. has the same value as the median and thus is not needed if you have the median.
d. it only uses two values in the data set.
7. Which of the following is used to examine the relationship between two qualitative variables?
a. variance
b. pivot table
c. correlation
d. mean
8. The symbol s2 represents
a. the population median
b. the sample variance
c. the population standard deviation
d. the population mean
9. If data is mound shaped symmetric with a mean of 70 and a standard deviation of 10, then 95% of the time you
will find a range smaller than…
a. 40
b. 70
c. 10
d. 1.645
10. What is the standard deviation of the following population of numbers? 2, 5, 6?
a. 1.57
b. 4
c. none of the other answers are correct
d. 2.16
11. Find the mean and median of the values 1, 13, 7, 5, 11, 9, 3. Using the rules in the notes, the data is
a. qualitative
b. symmetric
c. right skewed
d. left skewed
12. Suppose a population follows the bell-shaped distribution with =70 and =10, what percent of the values are
larger than 90?
a. 2.5%
b. 16%
c. 97.5%
d. none of the others are correct
13. You believe that the grade on an exam depends on the amount of hours studied. What does the correlation
measure?
a. the strength of the linear relationship between the two.
b. the intercept
c. the conditional probability of one qualitative variables given the other.
d. the range
14. A sample slope of 95,000 would indicate what about the strength of the relationship?
a. a strong positive relationship between the dependent and independent variables
b. nothing about the strength
c. a weak positive relationship.
d. a strong negative relationship.
15. Which of the following can be used to find the probability of a value of x in a binomial distribution regardless of
the value of n, p, and x?
a. a scatterplot
b. binomial formula
c. binomial table
d. empirical rule
16. The 97.5 percentile of a distribution has …
a. 97.5% of the values below it.
b. 97.5% of the values above it.
c. 95% of the values between it and the mean.
d. none of the other answers are correct
17. Given the table on the right, find the Pr (B1 or A3)
a. 0.09
b. 0.59
c. 0.64
d. none of the other answers are correct
B1
B2
A1
0.03
0.17
A2
0.41
0.19
A3
0.06
0.14
18. If A and B are independent, Pr(A) = 0.10, and Pr(B)=0.90, then what is the probability of A or B?
a. 0.91
b. 0.10
c. can not be determined
d. 0
19. If Pr(A) = 0.2, Pr (B) = 0.50, and Pr(A | B) = 0.0, then what is the probability of A and B?
a. 0
b. 0.10
c. 0.70
d. none of the other answers are correct.
20. Out of a graduating class of 100 high students who went to college, 40 of them majored in business. 15% of the
business majors graduated from college. 30% of the non-business majors graduated from college. You will choose a
person from those who graduated college, what is the probability that the student majored in business?
a. 0.40
b. none of the other answers are correct.
c. 1.20
d. 0.25
21. Suppose you have a binomial with n=10,000 and p=0.20. Assuming the distribution of the counts is moundshaped symmetric, what is the value of x on the 16th percentile?
a. none of the other answers are correct
b. 0.80
c. 1960
d. 2040
22. You are concerned about your grade on an exam. The exam consisted of 25 questions. Furthermore, suppose that
on any one question, there is a 90% chance that you will get it correct. What procedure would you use to determine
the probability of failing?
a. binomial probability table
b. the empirical rule
c. probability from pie charts
d. a scatter-plot
23. How many ways can you get exactly 4 successes out of 27 trials? Choose the appropriate substitution.

4! 
(0.60) 4 (0.40) 23
 27!(23!) 
a. 
b. none of the other answers are correct
 27! 

 4!(23!) 
c. 
 27! 
(0.60) 4 (0.40) 23
 4!(23!) 
d. 
24. Some multiple of the standard error is called
a. the standard deviation
b. the population mean
c. the margin of error
d. George (Hint: George says that he does not want to get involved. Choose another answer)
1a
2b
3c
4b
5d
6d
7b
8b
9a
10 c
11 b
12 a
13 a
14 b
15 b
16 a
17 c
18 a
19 a
20 d
21 c
22 a
23 c
24 c
25 any