a doctor orders 1 gram of a medication to be administered intravenously the available vial contains 200 milligrams per milliliter how many milliliters

HESI A2

HESI A2 Math Practice

1. A doctor orders 1 gram of a medication to be administered intravenously. The available vial contains 200 milligrams per milliliter. How many milliliters of the solution should be drawn up?

A. 4 milliliters
B. 5 milliliters
C. 10 milliliters
D. 20 milliliters

Correct answer: B

Rationale: 1 gram is equivalent to 1000 milligrams. The concentration of the medication is 200 milligrams per milliliter. To calculate the volume needed, divide the total amount of medication by the concentration: 1000 mg / 200 mg/mL = 5 mL. Therefore, 5 milliliters of the solution should be drawn up to administer 1 gram of the medication intravenously. Choice A (4 milliliters), Choice C (10 milliliters), and Choice D (20 milliliters) are incorrect because they do not accurately calculate the volume of the solution needed based on the concentration of the medication.

2. Tamison bought 20 stamps for 29¢ each and 40 stamps for 42¢ each. If she gave the postal worker $25, how much change did she receive?

A. $2.40
B. $2.80
C. $3.20
D. $3.60

Correct answer: A

Rationale: First, calculate the total cost of the 20 stamps bought at 29¢ each: 20 stamps * 29¢ = $5.80. Next, calculate the total cost of the 40 stamps bought at 42¢ each: 40 stamps * 42¢ = $16.80. The total cost of all stamps is $5.80 + $16.80 = $22.60. If Tamison gave $25 to the postal worker, her change is $25 - $22.60 = $2.40. Therefore, the correct answer is A. Option B, C, and D are incorrect as they do not reflect the correct change Tamison received after buying the stamps.

3. How many inches are in 1.5 yards?

A. 54 inches
B. 60 inches
C. 72 inches
D. 84 inches

Correct answer: A

Rationale: To convert yards to inches, you multiply the number of yards by 36 (since there are 36 inches in a yard). So, 1.5 yards × 36 inches/yard = 54 inches. Therefore, the correct answer is A. Choice B, C, and D are incorrect as they do not correctly convert yards to inches.

4. How many pounds are in 144 ounces?

A. 12 pounds
B. 10 pounds
C. 8 pounds
D. 9 pounds

Correct answer: D

Rationale: To convert ounces to pounds, you need to know that there are 16 ounces in a pound. Therefore, to find out how many pounds are in 144 ounces, you divide 144 by 16, which equals 9 pounds. Choice A, 12 pounds, is incorrect because it does not correctly divide the number of ounces by the conversion factor. Choices B and C, 10 pounds and 8 pounds respectively, are also incorrect as they do not utilize the correct conversion factor to calculate the number of pounds in 144 ounces.

5. If a train travels at 80 kilometers per hour, how many kilometers will it travel in 3 hours?

A. 240 kilometers
B. 160 kilometers
C. 240 kilometers
D. 210 kilometers

Correct answer: A

Rationale: To find the total distance traveled, you need to multiply the speed of the train by the time it travels. So, 80 km/h * 3 hours = 240 kilometers. Therefore, the correct answer is 240 kilometers. Choice B (160 kilometers) is incorrect because it is the result of multiplying the speed by 2 hours instead of 3. Choice C (240 kilometers) is the same as the correct answer, making it redundant. Choice D (210 kilometers) is incorrect as it is the result of multiplying the speed by 2.5 hours instead of 3.