Practice HESI A2 Math Test

Correct Answer: D

Rationale: 1 milliliter (mL) is equal to 1000 micrograms (mcg). Therefore, to find out how many milliliters are needed for 250 micrograms: 250 mcg � 1000 = 0.25 mL. So, the healthcare professional should draw up 0.25 milliliters of the drug to administer 250 micrograms subcutaneously. Choice A, 0.00025 milliliters, is incorrect as it is too small a volume for the required dosage. Choice B, 0.0025 milliliters, is also too small. Choice C, 0.025 milliliters, is 100 times greater than the correct answer of 0.25 milliliters. Therefore, the correct answer is 0.25 milliliters.

Correct Answer: B

Rationale: To find the volume of the triangular shelf, first calculate the area of the triangle (1/2 * base * height) which is (1/2 * 40 * 30) = 600 sq cm. Then, multiply this area by the depth of the shelf (600 * 25) = 15000 cu cm. Therefore, the volume of each shelf is 3750 cu cm. Choice A, C, and D are incorrect as they do not correctly calculate the volume based on the dimensions provided.

Correct Answer: C

Rationale: The metric system is based on powers of 10, making calculations and conversions easier because each unit increases or decreases by a factor of 10.

Correct Answer: B

Rationale: To find 6.4% of 32, first calculate 6.4% as a decimal (0.064) and then multiply it by 32 to get 2.048. When rounding to the tenths place, 2.048 is rounded to 2.1 because the digit after the tenths place is 8, which is equal to or greater than 5. Choice A is incorrect as it does not reflect the accurate calculation. Choices C and D are also incorrect because they do not match the correct result of multiplying 6.4% by 32 and rounding to the tenths place.

Correct Answer: C

Rationale: To calculate the distance Roger can drive on a full tank, multiply the number of gallons in his tank by the average miles per gallon his car gets. 16 gallons x 25 miles per gallon = 400 miles. Therefore, Roger can drive 400 miles on a full tank. Choice A (41 miles) is incorrect as it does not consider the tank's full capacity. Choice B (100 miles) is incorrect as it does not account for the full tank's capacity and the average miles per gallon. Choice D (320 miles) is incorrect as it miscalculates the total distance based on the given information.