Learning Center’s
Statistics 1300
Final Exam Review
Middlebush Room 12
Friday, May 8, 2009
2:00 – 4:00 p.m.
Note 1: In addition to these review problems, I would advise students to work through problems from the sample
finals posted on Blackboard.
Note 2: There will be a Q&A session on Tuesday, May 12 from 12:00 to 1:30 p.m. in Middlebush 206.
1. A student’s final grade can sometimes be affected in a negative way by missing too many classes throughout a
semester. To analyze the notion that the more days a student misses (x), the lower your final grade (y, in
percentage), the data below were collected from a random sample of 10 students.
x 2 1 10 5 25 12 7 40 22 0
y 84 95 85 75 54 58 81 70 62 91
22
124, 755, 3032, 58797, 8265xyx y xyΣ= Σ= Σ = Σ = Σ =
a) Find the equation of the least squares line.
b) What final grade percentage should be predicted for a student who misses 9 classes?
c) Find the sample correlation coefficient.
d) Assuming that, for each value of x, the corresponding y’s have the same variance, find the estimate for this
common variance.
2. Six subjects were selected at random, and the age and systolic blood pressure for each was recorded. Their ages
ranged from 43 to 70, and their blood pressures ranged from 120 to 152. Using this data, Minitab produced the
regression analysis output that is given below.
Regression Analysis: Pressure versus Age
The regression equation is
Pressure = 81.0 + 0.964 Age
Predictor Coef SE Coef T P
Constant 81.05 13.88 5.84 0.004
Age 0.9644 0.2381 4.05 0.015
S = 5.641 R-Sq = 80.4% R-Sq(adj) = 75.5%
Analysis of Variance
Source DF SS MS F P
Regression 1 522.21 522.21 16.41 0.015
Residual Error 4 127.29 31.82
Total 5 649.50
a) If we test the hypothesis 01
:0H
β
= against 1
:0
A
H
β
≠
, what is the p-value for the test?
b) Using .05
α
=, what would we conclude for the test in (a)?
c) If we test the hypothesis that blood pressure tends to increase with age, what is the p-value for the test?
3. Use the relative frequency histogram at the right
to answer the following questions. Read all
relative frequencies to the nearest 5%.
a) If there are 80 observations in the data set, how
many observations are between 30 and 50?
b) Find the median.
c) Based on the histogram, which should be larger,
the mean or the median? Why?
4. Find the standard deviation of the following
data set: {1, 4, 5, 9}.
9080706050403020100
30
20
10
0
C
1
Percent
5. Of the members of a particular Poker club, 60% play Hold ‘em regularly, 55% play Seven Card Stud regularly,
and 30% play both Hold ‘em and Seven Card Stud regularly.
a) If members are selected at random, what is the probability that he or she will play either Hold ‘em or Seven Card
Stud regularly?
b) Are the events “plays Hold ‘em regularly” and “plays Seven Card Stud regularly” independent? Explain.
c) Are the events “plays Hold ‘em regularly” and “plays Seven Card Stud regularly” mutually exclusive? Explain.
6. Suppose that 20% of professional comedians quit performing by the time they are 40 years of age.
a) If 15 professional comedians are selected at random, what is the probability that at least 5 will quit by age 40?
b) If 16 professional comedians are selected at random, what is the probability that exactly 2 will quit by age 40?
