Find x. 120:x = 40:0.5.

Correct Answer: C

Rationale: To find x, set up the proportion and solve for x: 120/x = 40/0.5. Cross multiply to get 120 * 0.5 = 40x. This simplifies to 60 = 40x. Divide by 40 to isolate x, giving x = 60/40 = 1. Therefore, the correct answer is C, which is 1. Choice A (60) is incorrect because it does not match the correct calculation. Choice B (0) is incorrect as the calculation results in x = 1, not 0. Choice D (25) is incorrect as it does not match the correct calculation of x = 1.

Correct Answer: B

Rationale: To find 20% of 150, you need to multiply 150 by 0.20: 150 0.20 = 30. Therefore, 20% of 150 is indeed 30. Choice A (25) is incorrect as it represents 20% of 125, not 150. Choice C (35) is incorrect as it represents more than 20% of 150. Choice D (20) is incorrect as it is the original percentage to find.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: C

Rationale: To find the result of dividing 0.9 by 3, we perform the division operation, which equals 0.3. Therefore, the correct answer is 0.3. Choice A (0) is incorrect as the result is not zero, but 0.3. Choice B (3) is incorrect as 0.9 divided by 3 is not 3 but 0.3. Choice D (9) is incorrect as 0.9 divided by 3 is not 9 but 0.3.

Correct Answer: C

Rationale: To calculate the number of mils, first, convert 1.5 grams to milligrams (1.5 grams = 1500 mg). Then, since 1 mil contains 500 mg, divide 1500 mg by 500 mg/mil, resulting in 3 mils required to contain 1.5 grams of substance. Choice A, 9, is incorrect because it miscalculates the conversion. Choice B, 2, is incorrect as it does not consider the correct conversion factor. Choice D, 5, is incorrect as it also miscalculates the conversion.