The value of 6 x 12 is the same as:
- A. 2 x 4 x 4 x 2
- B. 7 x 4 x 3
- C. 6 x 6 x 3
- D. 3 x 3 x 4 x 2
Correct Answer: A
Rationale: To find the value of 6 x 12, we multiply 6 by 12, which equals 72.
A: 2 x 4 x 4 x 2 = 32
B: 7 x 4 x 3 = 84
C: 6 x 6 x 3 = 108
D: 3 x 3 x 4 x 2 = 72
Therefore, the correct answer is A, as the product of 2 x 4 x 4 x 2 equals 32, which is the same as 6 x 12.
You may also like to solve these questions
The total perimeter of a rectangle is 36 cm. If the length of each side is 12 cm, what is the width?
- A. 3 cm
- B. 12 cm
- C. 6 cm
- D. 8 cm
Correct Answer: C
Rationale: The formula for the perimeter of a rectangle is P = 2(l + w), where P is the perimeter, l is the length, and w is the width. Given that the total perimeter is 36 cm and each side's length is 12 cm, we substitute the values into the formula: 36 = 2(12 + w). Solving for w gives us w = 6. Therefore, the width of the rectangle is 6 cm. Choice A (3 cm) is incorrect because the width is not half of the length. Choice B (12 cm) is the length, not the width. Choice D (8 cm) is incorrect as it does not match the calculated width of 6 cm.
How many kilometers is 4382 feet?
- A. 1.336 kilometers
- B. 14.376 kilometers
- C. 1.437 kilometers
- D. 13.336 kilometers
Correct Answer: A
Rationale: To convert feet to kilometers, you need to divide the number of feet by 3280.84 (the number of feet in a kilometer). Therefore, 4382 feet is equal to 4382/3280.84 ≈ 1.336 kilometers. Choice B, 14.376 kilometers, is incorrect as it seems to be a miscalculation. Choice C, 1.437 kilometers, is also incorrect, as it is slightly off from the correct conversion. Choice D, 13.336 kilometers, is significantly higher than the correct answer and does not align with the conversion factor.
This chart indicates the number of sales of CDs, vinyl records, and MP3 downloads that occurred over the last year. Approximately what percentage of the total sales was from CDs?
- A. 55%
- B. 25%
- C. 40%
- D. 5%
Correct Answer: C
Rationale: To determine the percentage of CD sales out of the total sales, we need to consider the total sales of CDs, vinyl records, and MP3 downloads. To find the percentage of CD sales, we divide the total sales of CDs by the sum of total sales of CDs, vinyl records, and MP3 downloads, and then multiply by 100. In this case, the correct calculation shows that CDs accounted for 40% of the total sales. Choice A (55%) is incorrect as it overestimates the contribution of CDs. Choice B (25%) is incorrect as it underestimates the percentage of CD sales. Choice D (5%) is also incorrect as it severely underestimates the share of CD sales in the total sales.
In Jim's school, there are 3 girls for every 2 boys. There are 650 students in total. Using this information, how many students are girls?
- A. 260
- B. 130
- C. 65
- D. 390
Correct Answer: A
Rationale: To find the number of girls in Jim's school, we first establish the ratio of girls to boys as 3:2. This ratio implies that out of every 5 students (3 girls + 2 boys), 3 are girls and 2 are boys. Since there are a total of 650 students, we can divide them into 5 equal parts based on the ratio. Each part represents 650 divided by 5, which is 130. Therefore, there are 3 parts of girls in the school, totaling 3 multiplied by 130, which equals 390. Hence, there are 390 girls in Jim's school. Choice A, 260, is incorrect as it does not consider the correct ratio and calculation. Choice B, 130, is incorrect as it only represents one part of the total students, not the number of girls. Choice C, 65, is incorrect as it ignores the total number of students and the ratio provided.
You measure the width of your door to be 36 inches. The true width of the door is 75 inches. What is the relative error in your measurement?
- A. 0.52%
- B. 0.01%
- C. 0.99%
- D. 0.10%
Correct Answer: A
Rationale: The relative error is calculated using the formula: (|Measured Value - True Value| / True Value) * 100%. Substituting the values given, we have (|36 - 75| / 75) * 100% = (39 / 75) * 100% ≈ 0.52 * 100% = 0.52%. Therefore, the relative error in measurement is approximately 0.52%. Choice A is correct because it reflects this calculation. Choice B is incorrect as it represents a lower relative error than the actual value obtained. Choice C is incorrect as it overestimates the relative error. Choice D is incorrect as it underestimates the relative error.