WGU D128 MATHEMATICS FOR ELEMENTARY EDUCATORS OA EXAM
ACTUAL EXAM 200 QUESTIONS AND CORRECT DETAILED ANSWERS|
ALREADY GRADED A+
Question 1
Which of the following numbers is a prime number?
A) 49
B) 51
C) 53
D) 55
E) 57
Correct Answer: C) 53
Rationale: A prime number is a natural number greater than 1 that
has no positive divisors other than 1 and itself. 49 = 7x7, 51 = 3x17,
55 = 5x11, and 57 = 3x19. Only 53 has no divisors other than 1 and
53.
Question 2
What is the least common multiple (LCM) of 6, 8, and 12?
A) 24
B) 36
C) 48
D) 72
E) 96
Correct Answer: A) 24
Rationale: To find the LCM, list multiples of each number:
Multiples of 6: 6, 12, 18, 24, 30...
Multiples of 8: 8, 16, 24, 32...
Multiples of 12: 12, 24, 36...
The smallest common multiple is 24.
Question 3
A recipe calls for 2/3 cup of flour. If you want to make 1 1/2 times the recipe,
how much flour do you need?
A) 1 cup
B) 1 1/3 cups
C) 1 1/2 cups
D) 1 2/3 cups
E) 2 cups
Correct Answer: A) 1 cup
Rationale: To find the amount of flour, multiply 2/3 by 1 1/2.
First, convert 1 1/2 to an improper fraction: 1 1/2 = 3/2.
,Now, multiply: (2/3) * (3/2) = 6/6 = 1.
So, you need 1 cup of flour.
Question 4
Which property of addition states that changing the grouping of addends
does not change the sum?
A) Commutative Property
B) Associative Property
C) Distributive Property
D) Identity Property
E) Inverse Property
Correct Answer: B) Associative Property
Rationale: The Associative Property of Addition states that (a + b) + c
= a + (b + c). Changing the grouping (parentheses) of the numbers
does not affect the sum.
Question 5
What is 0.05 expressed as a fraction in simplest form?
A) 1/5
B) 5/10
C) 1/20
D) 5/100
E) 1/50
Correct Answer: C) 1/20
Rationale: 0.05 means five hundredths, which can be written as
5/100. To simplify this fraction, divide both the numerator and the
denominator by their greatest common divisor, which is 5.
5÷5=1
100 ÷ 5 = 20
So, 5/100 simplifies to 1/20.
Question 6
A class has 25 students. If 60% of the students are girls, how many girls are
in the class?
A) 10
B) 12
C) 15
D) 18
E) 20
Correct Answer: C) 15
Rationale: To find 60% of 25, multiply 25 by 0.60 (or 60/100).
, 25 * 0.60 = 15.
So, there are 15 girls in the class.
Question 7
If the perimeter of a square is 36 cm, what is its area?
A) 9 cm²
B) 18 cm²
C) 36 cm²
D) 81 cm²
E) 144 cm²
Correct Answer: D) 81 cm²
Rationale: For a square, all four sides are equal. If the perimeter is 36
cm, then each side length is 36 cm / 4 = 9 cm.
The area of a square is side * side.
Area = 9 cm * 9 cm = 81 cm².
Question 8
Which of the following quadrilaterals has exactly one pair of parallel sides?
A) Rectangle
B) Square
C) Rhombus
D) Trapezoid
E) Parallelogram
Correct Answer: D) Trapezoid
Rationale: A trapezoid (or trapezium) is defined as a quadrilateral
with at least one pair of parallel sides. In the U.S. definition, it is a
quadrilateral with exactly one pair of parallel sides.
Question 9
What is the value of the expression 3² + (8 - 2) ÷ 3?
A) 5
B) 7
C) 9
D) 11
E) 13
Correct Answer: D) 11
Rationale: **Follow the order of operations (PEMDAS/BODMAS):
1. Parentheses/Brackets: (8 - 2) = 6
2. Exponents: 3² = 9
3. Division: 6 ÷ 3 = 2
ACTUAL EXAM 200 QUESTIONS AND CORRECT DETAILED ANSWERS|
ALREADY GRADED A+
Question 1
Which of the following numbers is a prime number?
A) 49
B) 51
C) 53
D) 55
E) 57
Correct Answer: C) 53
Rationale: A prime number is a natural number greater than 1 that
has no positive divisors other than 1 and itself. 49 = 7x7, 51 = 3x17,
55 = 5x11, and 57 = 3x19. Only 53 has no divisors other than 1 and
53.
Question 2
What is the least common multiple (LCM) of 6, 8, and 12?
A) 24
B) 36
C) 48
D) 72
E) 96
Correct Answer: A) 24
Rationale: To find the LCM, list multiples of each number:
Multiples of 6: 6, 12, 18, 24, 30...
Multiples of 8: 8, 16, 24, 32...
Multiples of 12: 12, 24, 36...
The smallest common multiple is 24.
Question 3
A recipe calls for 2/3 cup of flour. If you want to make 1 1/2 times the recipe,
how much flour do you need?
A) 1 cup
B) 1 1/3 cups
C) 1 1/2 cups
D) 1 2/3 cups
E) 2 cups
Correct Answer: A) 1 cup
Rationale: To find the amount of flour, multiply 2/3 by 1 1/2.
First, convert 1 1/2 to an improper fraction: 1 1/2 = 3/2.
,Now, multiply: (2/3) * (3/2) = 6/6 = 1.
So, you need 1 cup of flour.
Question 4
Which property of addition states that changing the grouping of addends
does not change the sum?
A) Commutative Property
B) Associative Property
C) Distributive Property
D) Identity Property
E) Inverse Property
Correct Answer: B) Associative Property
Rationale: The Associative Property of Addition states that (a + b) + c
= a + (b + c). Changing the grouping (parentheses) of the numbers
does not affect the sum.
Question 5
What is 0.05 expressed as a fraction in simplest form?
A) 1/5
B) 5/10
C) 1/20
D) 5/100
E) 1/50
Correct Answer: C) 1/20
Rationale: 0.05 means five hundredths, which can be written as
5/100. To simplify this fraction, divide both the numerator and the
denominator by their greatest common divisor, which is 5.
5÷5=1
100 ÷ 5 = 20
So, 5/100 simplifies to 1/20.
Question 6
A class has 25 students. If 60% of the students are girls, how many girls are
in the class?
A) 10
B) 12
C) 15
D) 18
E) 20
Correct Answer: C) 15
Rationale: To find 60% of 25, multiply 25 by 0.60 (or 60/100).
, 25 * 0.60 = 15.
So, there are 15 girls in the class.
Question 7
If the perimeter of a square is 36 cm, what is its area?
A) 9 cm²
B) 18 cm²
C) 36 cm²
D) 81 cm²
E) 144 cm²
Correct Answer: D) 81 cm²
Rationale: For a square, all four sides are equal. If the perimeter is 36
cm, then each side length is 36 cm / 4 = 9 cm.
The area of a square is side * side.
Area = 9 cm * 9 cm = 81 cm².
Question 8
Which of the following quadrilaterals has exactly one pair of parallel sides?
A) Rectangle
B) Square
C) Rhombus
D) Trapezoid
E) Parallelogram
Correct Answer: D) Trapezoid
Rationale: A trapezoid (or trapezium) is defined as a quadrilateral
with at least one pair of parallel sides. In the U.S. definition, it is a
quadrilateral with exactly one pair of parallel sides.
Question 9
What is the value of the expression 3² + (8 - 2) ÷ 3?
A) 5
B) 7
C) 9
D) 11
E) 13
Correct Answer: D) 11
Rationale: **Follow the order of operations (PEMDAS/BODMAS):
1. Parentheses/Brackets: (8 - 2) = 6
2. Exponents: 3² = 9
3. Division: 6 ÷ 3 = 2
