If 32% of n is 20.8, what is n?
- A. 64
- B. 65
- C. 66
- D. 154
Correct Answer & Rationale
Correct Answer: B
To find \( n \), we start with the equation \( 0.32n = 20.8 \). By dividing both sides by 0.32, we calculate \( n = \frac{20.8}{0.32} \), which simplifies to 65. Option A (64) is incorrect; it underestimates \( n \) by miscalculating the percentage. Option C (66) slightly overestimates \( n \), failing to accurately reflect the relationship between the percentage and the total. Option D (154) is far too high, indicating a misunderstanding of the percentage calculation. Thus, 65 is the only value that satisfies the equation.
To find \( n \), we start with the equation \( 0.32n = 20.8 \). By dividing both sides by 0.32, we calculate \( n = \frac{20.8}{0.32} \), which simplifies to 65. Option A (64) is incorrect; it underestimates \( n \) by miscalculating the percentage. Option C (66) slightly overestimates \( n \), failing to accurately reflect the relationship between the percentage and the total. Option D (154) is far too high, indicating a misunderstanding of the percentage calculation. Thus, 65 is the only value that satisfies the equation.
Other Related Questions
Marisol has 5 times as many books as Jerry. Jerry has 15 books. How many books does Marisol have?
- A. 10
- B. 20
- C. 75
- D. 225
Correct Answer & Rationale
Correct Answer: C
To determine how many books Marisol has, start by recognizing that she has 5 times the number of books Jerry has. Since Jerry has 15 books, you multiply 15 by 5: 15 × 5 = 75. Thus, Marisol has 75 books. Option A (10) is incorrect as it suggests Marisol has fewer books than Jerry. Option B (20) also underestimates her total, as it does not account for the multiplication factor of 5. Option D (225) overestimates the total by incorrectly multiplying the number of Jerry's books. Only option C accurately reflects the calculation based on the relationship between Marisol's and Jerry's books.
To determine how many books Marisol has, start by recognizing that she has 5 times the number of books Jerry has. Since Jerry has 15 books, you multiply 15 by 5: 15 × 5 = 75. Thus, Marisol has 75 books. Option A (10) is incorrect as it suggests Marisol has fewer books than Jerry. Option B (20) also underestimates her total, as it does not account for the multiplication factor of 5. Option D (225) overestimates the total by incorrectly multiplying the number of Jerry's books. Only option C accurately reflects the calculation based on the relationship between Marisol's and Jerry's books.
2 + (2 × 2) + 2 =
- A. 8
- B. 10
- C. 12
- D. 16
Correct Answer & Rationale
Correct Answer: A
To solve the expression 2 + (2 × 2) + 2, it’s essential to follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction). First, calculate the value inside the parentheses: 2 × 2 equals 4. Next, substitute this back into the expression: 2 + 4 + 2. Then, perform the addition from left to right: 2 + 4 equals 6, and then 6 + 2 equals 8. Options B (10), C (12), and D (16) are incorrect because they do not adhere to the proper order of operations or miscalculate the addition steps.
To solve the expression 2 + (2 × 2) + 2, it’s essential to follow the order of operations, often remembered by the acronym PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction). First, calculate the value inside the parentheses: 2 × 2 equals 4. Next, substitute this back into the expression: 2 + 4 + 2. Then, perform the addition from left to right: 2 + 4 equals 6, and then 6 + 2 equals 8. Options B (10), C (12), and D (16) are incorrect because they do not adhere to the proper order of operations or miscalculate the addition steps.
What is the product of 2,2/3 and 3,3/8?
- A. 5,5/11
- B. 6,1/24
- C. 7
- D. 9
Correct Answer & Rationale
Correct Answer: D
To find the product of 2,2/3 and 3,3/8, first convert the mixed numbers to improper fractions. 2,2/3 becomes 8/3 and 3,3/8 becomes 27/8. Multiplying these fractions gives (8/3) * (27/8) = 216/24 = 9. Option A (5,5/11) and Option B (6,1/24) are incorrect as they do not represent the product of the two numbers. Option C (7) is also incorrect, as it is less than the calculated product. Thus, the only valid result from the multiplication is 9, confirming the correct answer.
To find the product of 2,2/3 and 3,3/8, first convert the mixed numbers to improper fractions. 2,2/3 becomes 8/3 and 3,3/8 becomes 27/8. Multiplying these fractions gives (8/3) * (27/8) = 216/24 = 9. Option A (5,5/11) and Option B (6,1/24) are incorrect as they do not represent the product of the two numbers. Option C (7) is also incorrect, as it is less than the calculated product. Thus, the only valid result from the multiplication is 9, confirming the correct answer.
Of the following, which is closest to 17/6 + 6/17 ?
- A. 1
- B. 2
- C. 3
- D. 23
Correct Answer & Rationale
Correct Answer: C
To solve 17/6 + 6/17, we first find a common denominator, which is 102. Rewriting the fractions gives us (17*17)/(6*17) + (6*6)/(17*6) = 289/102 + 36/102 = 325/102. Dividing 325 by 102 yields approximately 3.19, which is closest to 3. Option A (1) is too low, as it does not account for the combined value of the fractions. Option B (2) is still below the calculated sum. Option D (23) is excessively high and not feasible given the values involved. Thus, option C (3) is the most accurate approximation.
To solve 17/6 + 6/17, we first find a common denominator, which is 102. Rewriting the fractions gives us (17*17)/(6*17) + (6*6)/(17*6) = 289/102 + 36/102 = 325/102. Dividing 325 by 102 yields approximately 3.19, which is closest to 3. Option A (1) is too low, as it does not account for the combined value of the fractions. Option B (2) is still below the calculated sum. Option D (23) is excessively high and not feasible given the values involved. Thus, option C (3) is the most accurate approximation.