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. Subtract 32 divided by 8\9.

A. 36
B. 32
C. 40
D. 44

Correct answer: A

Rationale: 32 ÷ (8\9) is the same as 32 × (9\8) = 36.

3. You need to repaint a cylindrical water tank with a diameter of 2 meters and a height of 3 meters. Assuming one can of paint covers 10 sq m, how many cans do you need to cover only the exterior surface?

A. 6 cans
B. 9 cans
C. 12 cans
D. 15 cans

Correct answer: C

Rationale: To find the surface area of the cylinder, calculate the lateral surface area using the formula 2πrh, where r is the radius (half of the diameter) and h is the height. Substituting the values, we get 2 * π * 1 * 3 = 6π square meters. Since each can covers 10 sq m, divide the total surface area by the coverage area per can: 6π / 10 ≈ 1.9 cans. Since you can't buy a fraction of a can, you would need to round up, so you would need 2 cans to cover the entire exterior surface. Therefore, you would need 2 * 6 = 12 cans in total. Choices A, B, and D are incorrect as they do not consider the correct surface area calculation or the rounding up to the nearest whole number of cans required.

4. What is the result of adding 6 3/4 + 8 1/6?

A. 14 11/12
B. 12 3/4
C. 12 3/24
D. 14 2/5

Correct answer: A

Rationale: To add mixed numbers, convert them to improper fractions: 6 3/4 = 27/4 and 8 1/6 = 49/6. Then, add the fractions to get 27/4 + 49/6 = 162/24 + 98/24 = 260/24 = 21 20/24 = 21 10/12 = 21 5/6 = 14 11/12. Therefore, the correct answer is 14 11/12. Choice B (12 3/4) is incorrect as it does not match the correct calculation. Choice C (12 3/24) is incorrect due to the erroneous denominator in the final fraction. Choice D (14 2/5) is incorrect as it does not correspond to the correct sum of the fractions.

5. The head nurse at the hospital has a team of six nurses and one phlebotomist. If the phlebotomist is responsible for 1/7 of the patients, what fraction of the patients is each nurse responsible for?

A. 1/6
B. 1/7
C. 1/8
D. 1/5

Correct answer: A

Rationale: The correct answer is A: 1/6. The phlebotomist is responsible for 1/7 of the patients, leaving 6/7 of the patients for the six nurses. To find out the fraction of patients each nurse is responsible for, divide the remaining patients (6/7) among the six nurses. This results in each nurse being responsible for 1/6 of the patients. Choice B, 1/7, is incorrect because that is the fraction assigned to the phlebotomist. Choices C and D, 1/8 and 1/5, are incorrect fractions and do not reflect the correct distribution of patients among the nurses.