Nokea
Solve for x in the equation: 3x - 5 = 16
- A. 7
- B. 5
- C. 8
- D. 9
Correct Answer: C
Rationale: To solve for x, add 5 to both sides of the equation: 3x - 5 + 5 = 16 + 5, which simplifies to 3x = 21. Next, divide both sides by 3: x = 21 · 3 = 7. Therefore, the correct answer is x = 7, making option A the correct choice. Option C, '8,' is incorrect as it is not the solution obtained from the correct calculations. Options B and D, '5' and '9,' are also incorrect and not the solution to the given equation.
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What is the difference between two negative numbers?
- A. Negative number
- B. Positive number
- C. Zero
- D. Not enough information
Correct Answer: B
Rationale: The correct answer is B: 'Positive number.' When you subtract one negative number from another negative number, the result can be a positive number. For example, the difference between -5 and -3 is 2, which is a positive number. Choice A, 'Negative number,' is incorrect because the result of subtracting two negative numbers can be positive. Choice C, 'Zero,' is incorrect because the difference between two negative numbers is not always zero. Choice D, 'Not enough information,' is incorrect because there is enough information to determine that the difference between two negative numbers can be a positive number.
What is the mode of the data set: 2, 3, 3, 4, 4, 4, 5?
- A. 2
- B. 3
- C. 4
- D. 5
Correct Answer: C
Rationale: The mode of a data set is the value that appears most frequently. In this data set (2, 3, 3, 4, 4, 4, 5), the number 4 appears three times, which is more frequent than any other number in the set. Therefore, the correct answer is 4. Choice A (2), B (3), and D (5) do not appear as frequently as 4 in the data set, so they are not the mode.
Half of a circular garden with a radius of 11.5 feet needs weeding. Find the area in square feet that needs weeding. Round to the nearest hundredth. Use 3.14 for π.
- A. 207.64
- B. 415.27
- C. 519.08
- D. 726.73
Correct Answer: B
Rationale: The area of a circle is given by the formula A = π r², where r is the radius. Since only half of the garden needs weeding, we calculate half the area.
Using the given value of π (3.14) and a radius of 11.5 feet:
A = 0.5 3.14 (11.5)²
A = 0.5 3.14 132.25
A = 0.5 415.27
A = 207.64 square feet.
Thus, the area that needs weeding is approximately 207.64 square feet, making option B the correct answer.
Choice A (207.64) is incorrect as it represents the total area of the circular garden, not just half of it. Choice C (519.08) and Choice D (726.73) are also incorrect as they do not reflect the correct calculation for finding the area of half the circular garden.
What is the median of the data set: 3, 5, 7, 9, 11?
- A. 3
- B. 7
- C. 9
- D. 5
Correct Answer: B
Rationale: To find the median of a set of numbers, you arrange them in ascending order and then find the middle value. Given the data set 3, 5, 7, 9, 11, when arranged in ascending order, becomes 3, 5, 7, 9, 11. The middle value in this set is 7, making it the median. Choice A (3) is the smallest value, not the middle value. Choice C (9) and Choice D (5) are not the middle values of the set either. Therefore, the correct answer is B (7).
What is the mean for the data set 16, 18, 17, 15, 19, 14, 12, 11, 10, 16, 18, and 17?
- A. 14.25
- B. 15.25
- C. 16
- D. 17
Correct Answer: C
Rationale: To find the mean of a data set, you add up all the values and then divide by the total number of values. In this case, the sum of the data set is 185. Dividing this sum by the total number of values (12) gives you a mean of 16. Therefore, the correct answer is 16. Choice A (14.25), Choice B (15.25), and Choice D (17) are incorrect because they do not accurately represent the average value of the given data set.