ATI Dosage Calculation RN Fundamentals Proctored
Exam Study Guide Actual Exam 2026/2027 –
Complete Exam-Style Questions with Detailed
Rationales | Pass Guaranteed – A+ Graded
[SECTION 1: Basic Dosage Calculations (Oral, Injectable) — Questions 1-15]
Q1: A provider orders Amoxicillin 500 mg PO every 8 hours. The pharmacy supplies
Amoxicillin oral suspension 250 mg/5 mL. How many mL should the nurse administer per dose?
A. 5 mL
B. 12.5 mL
C. 10 mL
D. 2.5 mL
Correct Answer: C
Rationale: To calculate the dosage, use the formula: Desired/Have × Quantity. Desired (500 mg)
/ Have (250 mg) × Quantity (5 mL) = 2 × 5 mL = 10 mL. Option A is the quantity per
concentration unit, not the total dose. Option B and D represent calculation errors (using wrong
quantity or miscalculation).
Q2: The provider orders Prednisone 7.5 mg PO daily. The medication is available in 5 mg
tablets. How many tablet(s) should the nurse administer?
A. 1 tablet
B. 1.5 tablets
C. 1.5 tablets
D. 2 tablets
Correct Answer: C
Rationale: The calculation is 7.5 mg / 5 mg = 1.5. Since the tablets are not scored, the nurse must
consult the pharmacist; however, in a dosage calculation exam, if the question implies a scored
tablet or asks strictly for the math, 1.5 is the mathematical result. In practice, 1.5 tablets is
,2
possible if the tablet is scored; otherwise, a different strength is needed. Option A is underdosing,
and Option D is overdosing.
Q3: A nurse is preparing to administer Heparin 5,000 units subcutaneously. The available vial is
Heparin 10,000 units/mL. How many mL should the nurse administer?
A. 2 mL
C. 0.5 mL
C. 1 mL
D. 0.25 mL
Correct Answer: C
Rationale: Using Desired/Have × Quantity: 5,000 units / 10,000 units × 1 mL = 0.5 mL. Option
A (2 mL) would be 20,000 units. Option C (1 mL) would be 10,000 units. Option D (0.25 mL)
would be 2,500 units.
Q4: The provider orders Digoxin 0.25 mg IV daily. The medication is available as Digoxin 0.5
mg/2 mL. How many mL should the nurse administer?
A. 2 mL
B. 0.5 mL
C. 1 mL
D. 0.25 mL
Correct Answer: C
Rationale: Calculation: Desired (0.25 mg) / Have (0.5 mg) × Quantity (2 mL) = 0.5 × 2 mL = 1
mL. Option A is the total volume of the vial, which would be a double dose. Option B would
result in 0.125 mg. Option D is a calculation error.
Q5: A client is prescribed Cephalexin 1 g PO every 6 hours. The pharmacy dispenses Cephalexin
500 mg capsules. How many capsules should the nurse administer?
A. 1 capsule
, 3
C. 2 capsules
C. 3 capsules
D. 4 capsules
Correct Answer: C
Rationale: First, convert grams to milligrams: 1 g = 1,000 mg. Then, Desired (1,000 mg) / Have
(500 mg) = 2 capsules. Option A is half the prescribed dose. Options C and D represent
miscalculation.
Q6: The order is for Morphine sulfate 4 mg IV push. The available vial is Morphine sulfate 10
mg/mL. How many mL should the nurse administer?
A. 0.4 mL
B. 0.25 mL
C. 0.4 mL
D. 2.5 mL
Correct Answer: C
Rationale: Calculation: Desired (4 mg) / Have (10 mg) × 1 mL = 0.4 mL. Option B would be 2.5
mg. Option D would be 25 mg. Option A is mathematically correct but listed twice as a
distractor; 0.4 mL is the correct value.
Q7: A client is ordered to receive Metoclopramide 10 mg IM every 6 hours. The medication is
available as Metoclopramide 5 mg/mL. How many mL should the nurse draw up?
A. 2 mL
C. 2 mL
C. 1 mL
D. 0.5 mL
Correct Answer: C