Statistics Quiz
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Quiz 1
Refer to the following time plot that shows the number of breeding
bald eagle pairs in the lower United States and answer the questions
1-2.
1. For which year is the number pairs of bald eagles is lowest according
to the above plot?
2. Write the approximate number of pairs of bald eagles in the year
2000.
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Refer to the following display for the questions 3-4
3. The total revenue received according to the above display is
approximately
________________________
4. The percentage of revenue contributed by the state is approximately
___________________________
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5. Approximately what percentage of the expenses is in the area of
operations and maintenance?
_________________________
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Refer to the following stem plot for the questions 6-10
The stem plot displays the number of hours that a sample of
15 students spent studying for a calculus final exam
0* 9
1*
1* 2333
1* 45
1* 6
1* 8899
2 * 0
2 * 2
2* 4
6. What is the mean of this data?
7. What is the median of this data?
8. What is the first quartile of this data?
9. What is the third quartile of this data?
10. What is the inter quartile range of this data?
11. It is discovered that 24 hours was a typographical error for 42
hours. How will this error change the answer for mean in the question
#?
12. It is discovered that 24 hours was a typographical error for 42
hours. How will this error change the answer for median in the
question #7?
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Use the following histogram for answering questions 13-16
The histogram refers to the family incomes of 100 families in a certain
county
13. Fill in the following table based on the information from the
above histogram.
Class (1000s of $$) MIDPOINT Frequency
0 income 50
50 income 100
100 income 150
150 income 200
200 income 250
250 income 300
300 income 350
350 income 400
400 income 450
450 income 500
500 income 550
550 income 600
14. Write the % families with income less than $50000
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15. Write an approximate value of the mean for the data
represented by this histogram.
16. Write the class that contains the median value for this data.
For the questions 17‐19 use the following sample data for the time that it took members of a search
committee to go through 6 applications, the time is in minutes.
12, 18, 23, 27, 28, 30
17. Find the mean x of this data.
18. Fill the following table
x x x 2 x x
12
18
23
27
28
30
19. Find the standard deviation s of this data.
20. A bag of candies contains 20 candies, 8 of which are red, 6 blue,
3 yellow, and 3 green. A candy is randomly drawn. Write the
probability that this candy will be red.
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21. Refer to the following table that shows the gender of faculty
members and their discipline areas in a certain college and answer the
questions 22-25
Male Female
STEM 78 42
HUMANITIES 65 70
BUSINESS 59 21
A faculty member is selected at random.
22. Find the probability that the randomly chosen faculty member is
a male.
23. Find the probability that the randomly chosen faculty member is
a male given that the choice is from Humanities.
24. Find the probability that the randomly chosen faculty member is
a male and teaches business.
25. Find the probability that the faculty member teaches business.
26. Two fair dice (one yellow and the green) are rolled. Find the
probability that the green die will have six dots facing up given that
the yellow die has six dots facing up.
27. Are the event six dots facing up on the yellow die and the event
six dots facing up on the green die independent?
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Use the following box plot for the questions 28-30. The box plot refers to
a sample of average monthly temperatures in degrees Fahrenheit for the
cities of San Diego and Minneapolis.
28. Which city has a greater variability in average monthly
temperatures?
29. Which city has the greater percentage of months with
temperatures over 55 degrees F?
30. Write the medians of the two box plots.
