Correct Answer: C

Rationale: The greatest common factor (GCF) of two numbers is the largest number that divides both numbers without leaving a remainder. To find the GCF of 12 and 18, we factorize each number: 12 = 2 x 2 x 3 and 18 = 2 x 3 x 3. The common factors are 2 and 3. The GCF is the product of these common factors, which is 6. Therefore, 6 is the greatest common factor of 12 and 18. Choice A (2) and Choice B (3) are factors of both numbers but not the greatest common factor. Choice D (9) is not a factor of both 12 and 18, making it incorrect.

Correct Answer: A

Rationale: To convert grams to pounds, you can use the conversion factor: 1 pound = 453.59237 grams. Therefore, to find the equivalent of 1,500 grams in pounds, divide 1,500 by 453.59237 to get approximately 3.3 pounds. Choice A is the correct answer because it accurately represents the conversion. Choices B, C, and D are duplicates and do not provide an alternative option.

Correct Answer: D

Rationale: Rationale: - The patient receives 150mg of medication every 4 hours. - To calculate how many milligrams the patient will receive in 24 hours, we need to determine how many times the medication is administered in 24 hours. - Since the medication is administered every 4 hours, there are 24 hours in a day, so the medication will be administered 24 / 4 = 6 times in 24 hours. - Therefore, the total amount of medication the patient will receive in 24 hours is 150mg x 6 = 900mg.

Correct Answer: D

Rationale: The runner left at 7:45 and returned at 10:00, which means he ran for 2 hours and 15 minutes (10:00 - 7:45). At an average speed of 6 mph, in 2.25 hours, he would have covered 6 mph * 2.25 hours = 13.5 miles. Therefore, the correct answer is 13.5 miles. Choices A, B, and C are incorrect because they incorrectly calculate the distance based on the time and speed provided in the question.

Correct Answer: B

Rationale: Given x=11, substitute into the expression: (11 + 44) / (2*11) = 55 / 22 = 2.5. Therefore, the correct answer is 2.5. Choice A (33) is incorrect as it does not represent the correct calculation. Choice C (13) is incorrect as it is not the result of the expression. Choice D (55/22) is incorrect as it is the same as the simplified form of the expression, not the answer to the calculation.