Correct Answer: C

Rationale: Out of the 100 patients, 30% were men. Since 10% of the men were overweight as children, 90% of the male patients were not overweight. Therefore, the number of male patients not overweight as children can be calculated as 30 (total male patients) x 0.90 = 27. Choices A, B, and D are incorrect because they do not accurately calculate the number of male patients who were not overweight as children based on the given information.

Correct Answer: C

Rationale: To determine the highest percentage, we need to calculate each option. The percentage in answer A is: 50 / 250 x 100 = 20%. The percentage in answer B is: 57 / 250 x 100 = 22.8%. The percentage in answer C is: (74 + 55) / 433 x 100 = 29.8%. The percentage in answer D is: 21 / 183 x 100 = 11.5%. Therefore, the correct answer is C, as it has the highest percentage of doctors among the staff at both hospitals. Choices A, B, and D are incorrect as they have lower percentages compared to choice C.

Correct Answer: C

Rationale: To find 1/6 of 500, multiply 500 by 1/6: (500)(1/6) = 500/6 = 83.33. Converting the fraction to a decimal gives 83.33. Rounding this to the nearest hundredth results in 83.33. Therefore, 83.33 milliliters of blood were used for further tests. Choice A is incorrect as it does not consider the decimal value of the fraction. Choice B is incorrect as it rounds to the tenths place, not the nearest hundredth. Choice D is incorrect as it rounds up unnecessarily, as the correct answer should be rounded to 83.33.

Correct Answer: C

Rationale: To solve the equation 3(x + 4) = 18, first distribute the 3 to both terms inside the parentheses: 3x + 12 = 18. Next, isolate the variable x by subtracting 12 from both sides: 3x = 6. Finally, divide by 3 to solve for x, giving x = 6. Choice A, x = 2, is incorrect as the correct solution is x = 6. Choices B (x = 4) and D (x = 8) are also incorrect as they do not satisfy the given equation.

Correct Answer: D

Rationale: To convert a decimal to a percentage, you multiply by 100. Therefore, to find the percentage equivalent of 0.0016, you would multiply 0.0016 by 100 to get 0.16%. This means that choice D, '0.16%', is the correct answer. Choices A, B, and C are incorrect because they do not correctly represent the percentage equivalent of 0.0016.