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Sample Stat Final, Fall 2007
( I make no claims that the actual final exam will be like this sample final. However, I
do use the sample final as a guide for making up the final exam.)
1) Calculator problem:10 male runners were tested to see if Gator-aid made them run
the 100 yard dash any faster. Their times were recorded without gator aid and then the
next day with Gator-aid. Do a hypothesis test at the 5% level on the data to see if the
Gator-aid made them run faster. ( Use symbols wo and w ) Do this problem with a
calculator, show no work.
Without GA
11.2
15
13
9
15.1
12
13.7
9.7
11
13
With GA
11
15.2
12.9
9.1
14.9
11.5
12
9.6
10.5
13
H0: __________________________
H1: ______________________
P-value:________
Interpret your results. ______________________
2) Show all work: The lottery commission wanted to find out if there is a
difference in the proportions of men and women who play the lottery. The
results are shown below. Find a 93% confidence interval for the difference
in the two proportions. Show all work.
Sample
1: Men
2: Women
 x x 
1
Z
2
2
X
1600
660
N
5000
3000
______________________________ Work
= _________________ (chart, no work)
Error = ___________________ work:
Confidence Interval: ___________________work:
g) Interpret your results ____________________
3) Show all work:You do a study of 182 bears and measure the length of their right
paws. You get a mean of 12.8 inches and a standard deviation of 3.56 inches. Use your
study to test the claim that the population mean of right bear paws is less than 13.1
inches. Use a 6% level of significance. Show all work.
H0: ______________________
H1: _______________________
Z x = _______________________
p-value = _______________
Interpret your results. __________________
4) Paired data is gathered concerning the number of hours a student studies for a statistics
test (X) verses the grade on the test (Y).
X (hours)
7
2
1
4
3
5.5
Y (grade)
95
60
60
82
62
90
Part I
a) make a scatter plot of the data. (hint: increment Y axis into divisions of 10 but start at
50)
b) Draw an approximate best-fit line through the points above
c) Calculate the best fit line on your calculator: ŷ = _______ + ______x
d) Calculate the residual at x = 7
________________
e) Use your model to find an estimate of the grade earned if you study for 6 hours.
f) Find R2 and interpret it’s meaning. R2 = ______________
g) what is the slope__________ interpret it’s meaning:_________________________
h) what is the y intercept ____________ interpret it’s meaning
_____________________
Par II Test the significance of the line in part “c” at the 5% level
a) P-value:_______
b) Circle one: significant
not significant