Statistics Exam
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FinalExamSTAT121Fall2020.docxSTAT 121 Final Exam Fall 2020
University of Business and Technology
College Of Business Administration
(Fall 2020)
Final Exam
Name:…………………………………………………… I.D ……………
Section: Date Course Code:
Introduction to Statistics
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The Questions |
Maximum Marks |
Marks Obtained |
|
Question 1 |
7 |
|
|
Question 2 |
4 |
|
|
Question 3 |
5 |
|
|
Totals |
16 |
|
INSTRUCTIONS:
The student will be subject to the enforcement of the university plagiarism regulation once it is proved that he broke it.
Question #1 (7 Marks). The following table shows the number of hours six students spent studying for a test (X) and their scores on that test (Y).
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|
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7 |
91 |
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5 |
85 |
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2 |
41 |
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3 |
64 |
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8 |
86 |
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5 |
62 |
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a) Complete the table above.
b) Calculate SS(X), SS(Y), SS(XY) and (r) for the given data.
Continue to the next page
c) Select the correct choice:
Based on the value of r, the variables X and Y have a
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weak positive correlation. |
weak negative correlation. |
|
moderate positive correlation. |
moderate negative correlation. |
|
high positive correlation |
high negative correlation |
Question #2 (4 Marks). From question 1, answer the following:
a) Calculate and and write the equation of the line of best fit.
b) If a student studied for four hours (), what is the expected score for the student?
Continue to the next page
Question #3 (5 Marks). Let X be the Discrete Random Variable for the number of cars owned by students in the college of engineering in UBT. The data collected is given in the table below. Find the mean, variance and standard deviation for the given data.
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X |
P (X) |
X P(X) |
X2 |
X2 P(X) |
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0 |
0.1 |
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1 |
0.6 |
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2 |
0.2 |
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3 |
0.1 |
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Total |
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