WGU C955 Probability and Statistics STUDY BUNDLE PACKAGE () (Verified by Expert)

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WGU C955 Probability and Statistics Pre Assessment Exam
Questions and Answers (Verified by Expert)

1. In a class of 25 students, the following test scores were obtained:
   31, 46, 49, 52, 55, 67, 68, 68, 69, 69, 71, 73, 73, 75, 75, 78, 79, 82, 84, 84, 85, 87,
   91, 92, 97
   Which statement is true about this distribution ANS The distribution is
   skewed tothe left.
2. In a class of 25 students, the following test scores were obtained:
   51, 59, 59, 59, 67, 68, 68, 69, 69, 71, 73, 73, 75, 75, 78, 79, 82, 84, 85, 85, 87, 91,
   92, 93, 93
   A histogram of interval width 10 starting with the interval [50, 60] was
   constructed using the above data.
   Which statement is true about this distribution as depicted by the histogram ANS It is a unimodal symmetric distribution.

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3. In a class of 25 students, the following scores were received on a quiz:
   3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 6, 6, 6, 7, 7, 8, 8, 8, 8, 8, 9, 9, 9, 9
   For this distribution, what is the most appropriate measure of central tendency ANS Either the mean or the median
4. The following 5-number summaries were obtained for two distributions, A
   and B:
   A 3.2 4.9 5.7 5.9 8.2
   B 2.7 5.1 5.7 6.9 7.5
   The distribution of A is skewed to the right, whereas the distribution of B is
   skewed to the left.
   How are the means of the two distributions related ANS The mean of A is
   higherthan the mean of B.
5. A study is conducted to determine if there is a difference in final exam
   scores in high school classrooms when different types of instruction are
   used.The two types of instruction included in the study are direct instruction

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and computer-based instruction.
What are the explanatory (X) and response (Y) variables for this study ANS
The type of instruction is the explanatory variable (X) and the test score is the
responsevariable (Y).

6. A store asked 350 of its customers whether they were satisfied with their
   service. The responses were also classified according to the gender of the
   customers.
   Satisfied Somewhat
   Satisfied Not
   Satisfied Total
   Male 60 60 50 170
   Female 45 20 115 180
   Total 105 80 165 350
   If a person wanted to study whether the level of satisfaction is related to
   or affected by gender, what is the appropriate table of conditional probabilities ANS Satisfied Somewhat
   Satisfied Not
   Satisfied Total
   Male 35.3% 35.3% 29.4% 100%
   Female 25.0% 11.1% 63.9% 100%

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WGU C955 Applied Probability and Statistics
All Terms and Formulas

1. Basic probability: #of total come# of total outcome in the sample space
2. P(B | A): conditional probability
3. P(A and B)=P(A) • P(B): multiplication rule- independent events
4. P(A and B)= P(A) • P(B|A): multiplication rule- dependent events
5. P(A or B)= P(A) + P(B): addition rule- Disjoint
6. P(A or B)= P(A) + P(B) – P(A and B): addition rule- non-Disjoint
7. product: The result of multiplying values.
8. factorization: The process of determining the prime factors of a composite
   number.
9. integer: “A number, (positive, negative, or zero), that can be represented without a fractional or a decimal component.”
10. superscript: A symbol (such as a number or letter) written above and imme-

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diately to the left or right of another character.

11. perfect square: “The product of any integer with itself. . So, a number is a this if it can be written as the square of an integer. For example, 3 * 3 = 9.”
12. expression: “A string of terms that are connected by division, addition, and
    subtraction operations.”
13. addition: Finding the total of two or more values.
14. interval: A set of numbers between two specified values.
15. difference: The result of one number being subtracted from another number.
16. multi-step expression: An expression or equation with more than two values and two or more operators that requires multiple steps to be solved.
17. discrete: “A collection of numbers whose values are distinct, separate, and
    unconnected.”
18. negative number: “A number whose value is less than zero. On the number
    line, they are to the left of zero.”
19. division: Splitting values into equal parts or groups.
20. estimation: Approximating a value for a calculation
21. radical sign: The symbol which indicates to take the square root of the number that follows.

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22. numbers: A word or symbol (such as ‘five’ or ’16’) that represents a specific
    amount or quantity.

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WGU C955 Probability and Statistics
Objective Assessment Exam Questions and Answers
(Verified by Expert)

1. What is 3/4 divided by 2/3?
   A) 9/8
   B) 5/12
   C) 5/7
   D) 6/7: 9/8
2. A county park has hiking paths with lengths of 1.05, 3.6, 3.17, and 2.2 miles.
   What is the total length, in miles, of hiking paths in the park?
   A) 9.02 miles
   B) 10.02 miles
   C) 10.12 miles
   D) 11.2 miles: 10.02 miles
3. If there are 2 tablespoons in 1 fluid ounce, how many tablespoons does the
   following calculation yield?

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4 fl oz – 1.5 tbsp
0.5 tbsp
1 tbsp
2.5 tbsp
6.5 tbsp: 6.5 tbsp

4. Solve for X:
   X – 5/4 = 2/3
   A) 3/12
   B) 7/12
   C) 10/12
   D) 23/12: 23/12
5. Solve for X:
   X+5/3=2/3
   A) -3
   B) -1
   C) 1
   D) 3: -1
6. Given the inequality:
   2y + 6 > 20
   Which graph is the solution?
   A) {{ y < 3 }}

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B) {{ y > 6 }}
C) {{ y > 7 }}
D) {{ y < 7 }}: {{ y > 7 }}

7. Which graph is the solution for y < 8?
   A) {{ unfilled circle on 8, arrow pointing left }}
   B) {{ filled circle on 8, arrow point left }}
   C) {{ unfilled circle on 8, arrow pointing right }}
   D) {{ filled circle on 8, arrow point right }}: {{ unfilled circle on 8, arrow pointing
   left }}
8. Which graph is the solution for 4y – 6 > 18?
   A) {{ y > 4 }}
   B) {{ y > 6 }}
   C) {{ y < 4 }} D) {{ y < 6 }}: {{ y > 6 }}
9. What is the correct line graph for y = 3x + 5?
   A) (0,5) to (2,11)
   B) (0,-5) to (2,-11)
   C) (0,3) to (2,5)
   D) (0,3) to (2,-7): (0,5) to (2,11)

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10. What is the correct line graph for y = -2x + 9?
    A) (0,9) to (4.5,0)
    B) (0,9) to (3,0)
    C) (0,-9) to (5,-19)
    D) (0,-9) to (5,-24): (0,9) to (4.5,0)
11. A normally distributed data set has a mean of 25 and a standard deviation
    of 2.
    Which percentage of the data falls between 23 and 25?
    A) 34.0
    B) 68.0
    C) 95.0
    D) 99.7: 34.0
12. A given data set is normally distributed with a mean of 200 and a standard
    deviation of 5.
    Which two values does 95% of the data fall between?

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WGU C955 Applied Probability and Statistics
Study Guide

1. Changing Improper Fractions and Mixed Numbers: Improper fractions can
   be converted to mixed numbers by following these steps:
   Write division problem with numerator divided by denominator.
   Divide to determine quotient and remainder.
   Write mixed number with the quotient as the whole number and the remainder as
   the numerator over the same denominator.
2. Changing Mixed Numbers Into Improper Fractions: Mixed numbers can also
   be converted to improper fractions by following these steps:
   Multiply the whole number by the denominator of the fraction.
   To the product given by step 1, add the number of the numerator.
   Write the result of step 2 as the numerator of the improper fraction. The denominator of the improper fraction should be the denominator of the original fraction.

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Simplify the improper fraction by diving the numerator and denominator by all
common factors.

3. Discrete Data: Has distinct values, can be counted, has unconnected points
   (dots)
4. Continuous data: Has values within a range, measured (not counted) does not
   have gaps between data points. (connected lines or curves)
5. Sign rule for Multiplication and division: 1. +# x +# = +#
6. -# x -# = +#
   A product or division of two numbers of the same sign will result in a positive
   number
7. -# x +# = -#
8. +# x -# = -#
   A product or division of two numbers of different signs will result in a negative
   number
9. Prime Number: A prime number is a number that has exactly two positive
   factors; 1 and itself.
10. Composite Number: A number that is not prime. It has 2 or more positive factor,
    including 1 and itself.

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8. Prime Factorization: Writing the number as a product of only prime numbers.
9. Greatest Common Factor (GCF): The larges number that divides all the given
   numbers evenly.
10. Multiples of a number: Numbers that can be obtained by multiplying the given
    number by 1, 2, 3, 4, etc.
11. Least Common Multiple (LCM): the smallest positive number that can be
    divided by the given numbers
12. Centigrade/Fahrenheit Conversions: C = (F – 32) X 5/9
    F = (C X 9/5) + 32
13. Unit Conversions for Household Measures of Volume: 1 tablespoon = 3
    teaspoons
    1 oz = 2 tablespoons
    1 cup = 8 oz
    1 pint = 2 cups
    1 quart = 1 pints
    1 gallon = 4 quarts