Nokea
Find x if 40:5 = 60:x.
- A. 12
- B. 7
- C. 1
- D. 8
Correct Answer: B
Rationale: To find x in the proportion 40:5 = 60:x, set up the equation: 40/5 = 60/x. Cross-multiply to solve for x: 40x = 60 * 5 => 40x = 300. Divide by 40 to isolate x: x = 300 / 40 = 7.5. However, x should be a whole number since it represents a quantity, so x = 7. Therefore, the correct answer is 7 (B). Choices A, C, and D are incorrect as they do not satisfy the proportion equation.
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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.
What is 39 · 8 · 7/6?
- A. 56/39
- B. 39/8
- C. 4 & 7/8
- D. 5 & 8/14
Correct Answer: A
Rationale: To solve the division problem, we need to remember the rule 'Dividing by a fraction is the same as multiplying by its reciprocal.' Therefore, 39 · 8 · 7/6 is equivalent to 39 · 8 6/7. Simplifying this gives (39 6) · (8 7) = 234 · 56 = 56/39. Therefore, the correct answer is A. Choices B, C, and D are incorrect as they do not correctly simplify the given division problem.
Convert 26°C to Fahrenheit.
- A. 78°F
- B. 72°F
- C. 80°F
- D. 85°F
Correct Answer: A
Rationale: To convert Celsius to Fahrenheit, the formula F = (9/5)C + 32 is used. Substituting 26°C into the formula: F = (9/5)(26) + 32 = 78.8°F, which rounds to 78°F. Therefore, the correct answer is 78°F. Choice B (72°F), Choice C (80°F), and Choice D (85°F) are incorrect as they do not result from the correct conversion calculation.
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.
How many centimeters are in 1 foot?
- A. 30.48
- B. 35
- C. 25
- D. 40
Correct Answer: A
Rationale: The correct answer is A, which is 30.48. To convert inches to feet, since there are 12 inches in a foot, you need to multiply the conversion factor from inches to centimeters (2.54 cm) by the number of inches in a foot (12). This gives 30.48 cm in 1 foot. Choice B, 35, is incorrect as it does not follow the correct conversion. Choices C and D, 25 and 40 respectively, are also incorrect conversions and do not align with the conversion factors provided in the question.