Given 15:x=3:8, find x.
- A. x=40
- B. x=20
- C. x=30
- D. x=10
Correct Answer: A
Rationale: To find x, we set up the proportion 15:x = 3:8. Cross multiply to get 15*8 = 3*x, which simplifies to 120 = 3x. Dividing by 3 on both sides gives x = 40. Therefore, x=40 is the correct answer. Choices B, C, and D are incorrect because they do not match the correct calculation. Option B results from incorrectly dividing 15 by 3 instead of multiplying it by 8. Option C comes from dividing 15 by 3, and Option D is the result of dividing 15 by 8 instead of multiplying by 3.
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An office manager makes photocopies for the entire staff each day. At the end of the week, she finds that the photocopy machine has made a total of 3,475 copies. If 6 people used the copier and each person made the same number of copies, how many copies did each person make?
- A. 579 copies
- B. 680 copies
- C. 670 copies
- D. 585 copies
Correct Answer: A
Rationale: To find out how many copies each person made, divide the total number of copies made (3,475) by the number of people who used the copier (6). This gives 579 copies per person (3,475 · 6 = 579). Therefore, each person made 579 copies. Choices B, C, and D are incorrect as they do not result from the correct division of the total number of copies by the number of people who used the copier.
Which of the following is equivalent to 0.0009?
- A. 0.009%
- B. 0.9%
- C. 0.09%
- D. 9%
Correct Answer: C
Rationale: To convert 0.0009 to a percentage, you need to multiply by 100. This gives 0.0009 as 0.09%. Therefore, choice C is the correct answer. Choice A, 0.009%, is incorrect because it represents 0.009, not 0.0009. Choice B, 0.9%, is incorrect as it represents 0.9, which is a different value. Choice D, 9%, is also incorrect as it represents 9, not 0.0009.
Change the following percentage to a decimal: 58%
- A. 0.58
- B. 5
Correct Answer: A
Rationale: To convert a percentage to a decimal, move the decimal point two places to the left. Therefore, 58% as a decimal is 0.58. Choice B, 5, is incorrect as it does not represent the conversion of a percentage to a decimal. Choices C and D, both 0, are also incorrect as they do not reflect the correct conversion of 58% to a decimal.
A patient needs to take 2 tablets for every 30 pounds of body weight. If they weigh 150 pounds, how many tablets should they take?
- A. 5
- B. 10
- C. 15
- D. 20
Correct Answer: B
Rationale: Rationale:
- The patient needs to take 2 tablets for every 30 pounds of body weight.
- If the patient weighs 150 pounds, we can calculate the number of tablets needed by dividing the weight by 30 and then multiplying by 2.
- 150 pounds / 30 pounds = 5
- 5 x 2 = 10 tablets
- Therefore, the patient should take 10 tablets.
What is the result of dividing 40.3 by 4.8?
- A. 7.5
- B. 8.4
- C. 6.2
- D. 9.1
Correct Answer: B
Rationale: To divide 40.3 by 4.8, you perform the calculation: 40.3 · 4.8 ≈ 8.4. Therefore, the correct answer is 8.4. Choice A (7.5) is incorrect as it is the result of dividing 40.3 by 5.4. Choice C (6.2) is incorrect as it is the result of dividing 40.3 by 6.5. Choice D (9.1) is incorrect as it is the result of dividing 40.3 by 4.4.