Nokea
Solve for x: 3(x - 5) = 2(x + 3)
- A. x = 3
- B. x = 6
- C. x = 9
- D. x = 12
Correct Answer: A
Rationale: To solve the equation 3(x - 5) = 2(x + 3) for x, start by distributing the terms inside the parentheses. This gives you 3x - 15 = 2x + 6. Next, combine like terms by moving all terms with x to one side and the constants to the other side. Subtracting 2x from both sides gives x - 15 = 6. Finally, adding 15 to both sides results in x = 21. Therefore, the correct answer is A: x = 3. Choices B, C, and D are incorrect as they do not result from the correct calculations of the equation.
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What is 4.6 rounded to the nearest integer?
- A. 3
- B. 4
- C. 5
- D. 6
Correct Answer: C
Rationale: When rounding a decimal number to the nearest integer, if the decimal part is 0.5 or greater, we round up to the next integer; if it is less than 0.5, we round down. In this case, 4.6 is closer to 5 than to 4 because it is exactly halfway between the two integers. Therefore, when rounding 4.6 to the nearest integer, we round up to 5. Choice A (3), B (4), and D (6) are incorrect as they are not the nearest integer to 4.6.
A quantity increases from 40 to 60. Express this increase as a percentage.
- A. 26%
- B. 50%
- C. 35%
- D. 12%
Correct Answer: B
Rationale: To calculate the percentage increase, use the formula:
Percentage Increase = ((New Value - Original Value) / Original Value) x 100
Substitute the values:
((60 - 40) / 40) x 100 = (20 / 40) x 100 = 0.5 x 100 = 50%
Therefore, the correct answer is 50%.
Choice A (26%) is incorrect as the percentage increase is not 26%. Choice C (35%) is incorrect as the percentage increase is not 35%. Choice D (12%) is incorrect as the percentage increase is not 12%.
Alan currently weighs 200 pounds, but he wants to lose weight to get down to 175 pounds. What is the difference in kilograms? (1 pound is approximately equal to 0.45 kilograms.)
- A. 9 kg
- B. 11.25 kg
- C. 78.75 kg
- D. 90 kg
Correct Answer: B
Rationale: The difference between Alan's current weight of 200 pounds and his goal weight of 175 pounds is 25 pounds (200 pounds - 175 pounds). To convert pounds to kilograms, you multiply the number of pounds by 0.45 (not divide by 2.2). Thus, 25 pounds is approximately 11.25 kilograms (25 pounds x 0.45). Therefore, the difference in kilograms is 11.25 kg. Choice A is incorrect because it miscalculates the conversion. Choices C and D are significantly higher values and do not reflect the correct conversion from pounds to kilograms.
After taking a certain antibiotic, Dr. Lee observed that 30% of all his patients developed an infection. He further noticed that 5% of those patients required hospitalization to recover from the infection. What percentage of Dr. Lee's patients were hospitalized after taking the antibiotic?
- A. 1.50%
- B. 5%
- C. 15%
- D. 30%
Correct Answer: A
Rationale: To find the percentage of Dr. Lee's patients hospitalized, you need to calculate 5% of the 30% who developed an infection. 5% of 30% is 1.5%. Therefore, 1.5% of Dr. Lee's patients were hospitalized. Choice A is correct. Choices B, C, and D are incorrect because they do not accurately reflect the calculation of the percentage of patients requiring hospitalization after taking the antibiotic.
Kimberley earns $10 an hour babysitting, and after 10 p.m., she earns $12 an hour, with the amount paid being rounded to the nearest hour accordingly. On her last job, she worked from 5:30 p.m. to 11 p.m. In total, how much did Kimberley earn on her last job?
- A. $45
- B. $57
- C. $62
- D. $42
Correct Answer: C
Rationale: Kimberley worked from 5:30 p.m. to 11 p.m., which is a total of 5.5 hours before 10 p.m. (from 5:30 p.m. to 10 p.m.) and 1 hour after 10 p.m. The earnings she made before 10 p.m. at $10 an hour was 5.5 hours * $10 = $55. Her earnings after 10 p.m. for the rounded hour were 1 hour * $12 = $12. Therefore, her total earnings for the last job were $55 + $12 = $67. Since the amount is rounded to the nearest hour, the closest rounded amount is $62. Therefore, Kimberley earned $62 on her last job. Choice A is incorrect as it does not consider the additional earnings after 10 p.m. Choices B and D are incorrect as they do not factor in the hourly rates and the total hours worked accurately.