# Statistics Homework

NEED DONE BY SAT 3/30/13

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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
500  income

10050  income
150100  income
200150  income
250200  income
300250  income
350300  income
400350  income
450400  income
500450  income
550500  income
600550  income

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   xx     2xx 
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.