Nokea
Solve for x: 3(x - 1) = 2(3x - 9)
- A. x = 2
- B. x = 8/3
- C. x = -5
- D. x = 5
Correct Answer: D
Rationale: To solve the equation 3(x - 1) = 2(3x - 9), first distribute and simplify both sides to get 3x - 3 = 6x - 18. Next, subtract 3x from both sides to get -3 = 3x - 18. Then, add 18 to both sides to obtain 15 = 3x. Finally, divide by 3 to find x = 5. Therefore, the correct answer is x = 5. Choices A, B, and C are incorrect because they do not represent the correct solution to the given equation after proper algebraic manipulation.
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While at the local ice skating rink, Cora went around the rink 27 times in total. She slipped and fell 20 of the 27 times she skated around the rink. What approximate percentage of the times around the rink did Cora not slip and fall?
- A. 37%
- B. 74%
- C. 26%
- D. 15%
Correct Answer: C
Rationale: To find the approximate percentage of the times Cora did not slip and fall, subtract the times she fell (20) from the total times around the rink (27), which gives 7. Then, divide the number of times she did not slip and fall (7) by the total times around the rink (27) and multiply by 100 to get the percentage. So, 7 divided by 27 equals 0.259, which rounds to approximately 26%. Therefore, the correct answer is 26%. Choice A (37%) is incorrect because it does not reflect the calculation based on the given information. Choice B (74%) is incorrect as it is not the result of the correct calculation. Choice D (15%) is incorrect as it does not match the calculated percentage based on the scenario provided.
How many centimeters are in 7 meters?
- A. 7 m = 7 cm
- B. 7 m = 70 cm
- C. 7 m = 700 cm
- D. 7 m = 7000 cm
Correct Answer: C
Rationale: The prefix 'centi-' means one-hundredth. In the metric system, 1 meter is equal to 100 centimeters. Therefore, to convert meters to centimeters, you multiply the number of meters by 100. In this case, 7 meters is equal to 7 * 100 = 700 centimeters. Choice A is incorrect as it does not consider the conversion factor properly. Choice B is incorrect as it only accounts for a factor of 10 instead of 100. Choice D is incorrect as it overestimates the conversion by a factor of 10.
A rectangular solid box has a square base with a side length of 5 feet and a height of h feet. If the volume of the box is 200 cubic feet, which of the following equations can be used to find h?
- A. 5h = 200
- B. 5h² = 200
- C. 25h = 200
- D. h = 200 · 5
Correct Answer: C
Rationale: The volume formula for a rectangular solid is V = l w h. In this case, the length and width are both 5 feet. Substituting the values into the formula gives V = 5 5 h = 25h = 200. Therefore, h = 200 · 25 = 8. Option A is incorrect because the product of length, width, and height is not directly equal to the volume. Option B is incorrect as squaring the height is not part of the volume formula. Option D is incorrect as it oversimplifies the relationship between height and volume, not considering the base dimensions.
A patient requires a 30% decrease in their medication dosage. Their current dosage is 340 mg. What will their dosage be after the decrease?
- A. 70 mg
- B. 238 mg
- C. 270 mg
- D. 340 mg
Correct Answer: B
Rationale: To calculate a 30% decrease of 340 mg, multiply 340 by 0.30 to get 102. Subtracting 102 from 340 gives a new dosage of 238 mg. Choice A (70 mg) is incorrect as it represents a 80% decrease, not 30%. Choice C (270 mg) is incorrect as it does not reflect a decrease but rather the original dosage. Choice D (340 mg) is incorrect as it is the original dosage and not reduced by 30%.
The table below shows the number of books checked out from a library over the course of 4 weeks. Which equation describes the relationship between the number of books (b) and weeks (w)?
- A. b = 10w + 2
- B. b = 5w + 10
- C. b = 8w + 12
- D. b = 4w + 20
Correct Answer: B
Rationale: The relationship between the number of books and weeks is best described by the equation b = 5w + 10. This is because the initial value of books checked out is 10, which indicates that even with 0 weeks, there are already 10 books checked out. The rate at which books are checked out per week is 5, as indicated by the coefficient of w. Therefore, the correct equation should be b = 5w + 10. Choices A, C, and D are incorrect because they do not represent the correct initial value or rate of increase for the given scenario.