Solve for x: 4(2x - 6) = 10x - 6
- A. x = 5
- B. x = -7
- C. x = -9
- D. x = 10
Correct Answer: C
Rationale: To solve the equation 4(2x - 6) = 10x - 6, first distribute 4 into the parentheses: 8x - 24 = 10x - 6. Next, simplify the equation by rearranging terms: 8x - 10x = -6 + 24, which gives -2x = 18. Solving for x by dividing by -2 on both sides gives x = -9. Therefore, the correct answer is x = -9. Choice A (x = 5), Choice B (x = -7), and Choice D (x = 10) are incorrect solutions obtained by errors in solving the equation.
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A farmer plans to install fencing around a certain field. If each side of the hexagonal field is 320 feet long, and fencing costs $1.75 per foot, how much will the farmer need to spend on fencing material to enclose the perimeter of the field?
- A. $2,240
- B. $2,800
- C. $3,360
- D. $4,480
Correct Answer: C
Rationale: To find the perimeter of a hexagonal field with 6 sides, multiply the length of one side (320 feet) by the number of sides (6): 320 x 6 = 1920 feet. The total cost of the fencing material can be calculated by multiplying the perimeter by the cost per foot: 1920 feet x $1.75 = $3360. Therefore, the farmer will need to spend $3,360 on fencing material to enclose the perimeter of the field. Choice A, B, and D are incorrect as they do not accurately calculate the total cost based on the given measurements and cost per foot.
Mathew has to earn more than 96 points on his high school entrance exam in order to be eligible for varsity sports. Each question is worth 3 points, and the test has a total of 40 questions. Let x represent the number of test questions. How many questions can Mathew answer incorrectly and still qualify for varsity sports?
- A. x > 32
- B. x > 8
- C. 0 ≤ x < 8
- D. 0 ≤ x ≤ 8
Correct Answer: C
Rationale: To determine the number of correct answers Mathew needs, solve the inequality: 3x > 96. This simplifies to x > 32. Therefore, Mathew must answer more than 32 questions correctly to qualify for varsity sports. Since the test consists of 40 questions, he can afford to answer at most 40 - 32 = 8 questions incorrectly. Therefore, the correct answer is 0 ≤ x < 8. Option A (x > 32) is incorrect as it suggests Mathew needs to answer more than 32 questions correctly, which is not the case. Option B (x > 8) is also incorrect as it does not account for the total number of questions in the test. Option D (0 ≤ x ≤ 8) is incorrect as it includes the possibility of answering all questions incorrectly, which is not allowed for Mathew to qualify for varsity sports.
Veronica has to create the holiday schedule for the neonatal unit at her hospital. 35% of her staff will be unavailable during the holidays, and of the remaining staff, only 20% are certified to work in the neonatal unit. What percentage of the total staff is certified and available to work?
- A. 7%
- B. 13%
- C. 65%
- D. 80%
Correct Answer: B
Rationale: The correct answer is 13%. To find the percentage of the total staff that is certified and available to work, we first calculate the percentage of staff available, which is 100% - 35% = 65%. Then, we find the percentage of the available staff that is certified, which is 20% of 65% = 0.20 0.65 = 0.13, or 13%.
Simplify the following expression:
3 (1/6) - 1 (5/6)
- A. 2 (1/3)
- B. 1 (1/3)
- C. 2 (1/9)
- D. 5/6
Correct Answer: B
Rationale: To simplify:
First, subtract the whole numbers: 3 - 1 = 2.
Then, subtract the fractions: (1/6) - (5/6) = - (4/6) = - (2/3).
Now, subtract (2 - 2/3) = 1 (1/3).
Given the double bar graph shown below, which of the following statements is true?
- A. Group A is negatively skewed, while Group B is approximately normal.
- B. Group A is positively skewed, while Group B is approximately normal.
- C. Group A is approximately normal, while Group B is negatively skewed.
- D. Group A is approximately normal, while Group B is positively skewed.
Correct Answer: B
Rationale: The correct answer is B. In a double bar graph, Group A is positively skewed, meaning its data is clustered on the left and has a tail extending to the right. On the other hand, Group B displays a normal distribution where the data is evenly distributed around the mean. Choices A, C, and D are incorrect as they inaccurately describe the skewness and distribution of the data in Group A and Group B.