Correct Answer: C

Rationale: To calculate the final dosage, first find 1/5 of 310 mg, which is 62 mg, and subtract it from the original dosage. This gives 310 mg - 62 mg = 248 mg. Then, subtract an additional 20 mg from the result to get the final dosage: 248 mg - 20 mg = 228 mg. Therefore, the patient's final dosage is 228 mg. Choice A (20 mg) is incorrect because it only considers the second reduction of 20 mg and misses the initial reduction by 1/5. Choice B (42 mg) is incorrect as it miscalculates the reduction amounts. Choice D (248 mg) is incorrect as it does not account for the second reduction of 20 mg.

Correct Answer: C

Rationale: To calculate the final dosage, first find 1/5 of 310 mg, which is 62 mg, and subtract it from the original dosage. This gives 310 mg - 62 mg = 248 mg. Then, subtract an additional 20 mg from the result to get the final dosage: 248 mg - 20 mg = 228 mg. Therefore, the patient's final dosage is 228 mg. Choice A (20 mg) is incorrect because it only considers the second reduction of 20 mg and misses the initial reduction by 1/5. Choice B (42 mg) is incorrect as it miscalculates the reduction amounts. Choice D (248 mg) is incorrect as it does not account for the second reduction of 20 mg.

Correct Answer: A

Rationale: To convert Stella's weight from kilograms to pounds, you multiply her weight in kilograms (56) by the conversion factor (2.2): 56 2.2 = 123.2 pounds. Since we need to find the approximate weight in pounds, the closest option is 123 pounds, making choice A the correct answer. Choices B, C, and D are incorrect because they do not reflect the accurate conversion of Stella's weight from kilograms to pounds.

Correct Answer: C

Rationale: To find the distance traveled by the train, we use the formula Distance = Speed x Time. Given that the train travels at 60 miles per hour for 2 hours, the calculation would be 60 miles/hour x 2 hours = 120 miles. Therefore, the correct answer is 120 miles. Choice A (60 miles) is incorrect because it only represents the speed of the train, not the total distance traveled. Choice B (100 miles) is incorrect as it does not account for the full 2 hours of travel. Choice D (200 miles) is incorrect as it overestimates the distance by multiplying the speed by the time incorrectly.

Correct Answer: A

Rationale: To calculate the total monthly earnings, we first find the commission earned on $5,000 sales, which is 3% of $5,000 = $150. Adding this commission to the $2,000 base salary gives a total of $2,000 + $150 = $2,150. Therefore, the correct total monthly earnings are $2,500. Choice B ($2,150) is incorrect because it only includes the base salary and the commission but miscalculates the total. Choices C ($2,100) and D ($2,300) are also incorrect as they do not account for the correct calculation of the commission on sales.