ATI RN Dosage Calculation Practice Exam
2025/2026 Actual Medication Math Questions
with Verified Answers & Step-by-Step
Rationales | Graded A+
Section 1: Oral Medication Calculations (Questions 1–5)
1. A nurse is preparing to administer sucralfate 1 g PO twice daily. Available is sucralfate
1,000 mg tablets. How many tablets should the nurse administer per dose?
1 tablet
Rationale:
o Step 1: Identify the ordered dose: 1 g = 1,000 mg (since 1 g = 1,000 mg).
o Step 2: Available dose is 1,000 mg per tablet.
o Step 3: Calculate tablets per dose: 1,000 mg ÷ 1,000 mg/tablet = 1 tablet.
o No rounding needed as the result is a whole number.
2. A nurse is preparing to administer diphenhydramine 25 mg PO every 6 hr. Available is
diphenhydramine syrup 12.5 mg/5 mL. How many mL should the nurse administer per
dose?
10 mL
Rationale:
o Step 1: Ordered dose: 25 mg.
o Step 2: Available concentration: 12.5 mg/5 mL.
o Step 3: Set up the calculation: (25 mg ÷ 12.5 mg) × 5 mL = 2 × 5 mL = 10 mL.
o No rounding needed as the result is a whole number.
3. A nurse is preparing to administer quinapril 20 mg PO. Available is quinapril 40 mg
tablets. How many tablets should the nurse administer?
0.5 tablet
Rationale:
o Step 1: Ordered dose: 20 mg.
o Step 2: Available dose: 40 mg per tablet.
o Step 3: Calculate tablets: 20 mg ÷ 40 mg/tablet = 0.5 tablet.
o Step 4: Round to the nearest tenth: 0.5 (already at tenth).
o Note: Ensure the tablet is scored for splitting.
4. A nurse is preparing to administer dexamethasone 3 mg PO every 12 hr. Available is
dexamethasone oral solution 0.5 mg/5 mL. How many mL should the nurse administer
per dose?
30 mL
Rationale:
o Step 1: Ordered dose: 3 mg.
, o Step 2: Available concentration: 0.5 mg/5 mL.
o Step 3: Calculate mL: (3 mg ÷ 0.5 mg) × 5 mL = 6 × 5 mL = 30 mL.
o No rounding needed as the result is a whole number.
5. A nurse is preparing to administer ribavirin 600 mg PO every 12 hr. Available is ribavirin
200 mg/tablet. How many tablets should the nurse administer per dose?
3 tablets
Rationale:
o Step 1: Ordered dose: 600 mg.
o Step 2: Available dose: 200 mg/tablet.
o Step 3: Calculate tablets: 600 mg ÷ 200 mg/tablet = 3 tablets.
o No rounding needed as the result is a whole number.
Section 2: Parenteral Medication Calculations (Questions 6–
10)
6. A nurse is preparing to administer cefazolin 250 mg IM. Available is cefazolin powder
500 mg vial, reconstituted with 2 mL sterile water to yield 225 mg/mL. How many mL
should the nurse administer? (Round to the nearest tenth.)
1.1 mL
Rationale:
o Step 1: Ordered dose: 250 mg.
o Step 2: Available concentration: 225 mg/mL.
o Step 3: Calculate mL: 250 mg ÷ 225 mg/mL = 1.111 mL.
o Step 4: Round to the nearest tenth: 1.111 ≈ 1.1 mL.
7. A nurse is preparing to administer fentanyl 50 mcg IM. Available is fentanyl injection
0.05 mg/mL. How many mL should the nurse administer? (Round to the nearest whole
number.)
1 mL
Rationale:
o Step 1: Ordered dose: 50 mcg = 0.05 mg (since 1 mg = 1,000 mcg).
o Step 2: Available concentration: 0.05 mg/mL.
o Step 3: Calculate mL: 0.05 mg ÷ 0.05 mg/mL = 1 mL.
o No rounding needed as the result is a whole number.
8. A nurse is preparing to administer enoxaparin 30 mg subcutaneous. Available is
enoxaparin injection 60 mg/0.6 mL. How many mL should the nurse administer?
0.3 mL
Rationale:
o Step 1: Ordered dose: 30 mg.
o Step 2: Available concentration: 60 mg/0.6 mL = 100 mg/mL (60 ÷ 0.6 = 100).
o Step 3: Calculate mL: 30 mg ÷ 100 mg/mL = 0.3 mL.
o No rounding needed as the result is exact.
9. A nurse is preparing to administer hydralazine 0.2 mg/kg IM to a client who weighs 84
lb. Available is hydralazine 20 mg/mL. How many mL should the nurse administer?
2025/2026 Actual Medication Math Questions
with Verified Answers & Step-by-Step
Rationales | Graded A+
Section 1: Oral Medication Calculations (Questions 1–5)
1. A nurse is preparing to administer sucralfate 1 g PO twice daily. Available is sucralfate
1,000 mg tablets. How many tablets should the nurse administer per dose?
1 tablet
Rationale:
o Step 1: Identify the ordered dose: 1 g = 1,000 mg (since 1 g = 1,000 mg).
o Step 2: Available dose is 1,000 mg per tablet.
o Step 3: Calculate tablets per dose: 1,000 mg ÷ 1,000 mg/tablet = 1 tablet.
o No rounding needed as the result is a whole number.
2. A nurse is preparing to administer diphenhydramine 25 mg PO every 6 hr. Available is
diphenhydramine syrup 12.5 mg/5 mL. How many mL should the nurse administer per
dose?
10 mL
Rationale:
o Step 1: Ordered dose: 25 mg.
o Step 2: Available concentration: 12.5 mg/5 mL.
o Step 3: Set up the calculation: (25 mg ÷ 12.5 mg) × 5 mL = 2 × 5 mL = 10 mL.
o No rounding needed as the result is a whole number.
3. A nurse is preparing to administer quinapril 20 mg PO. Available is quinapril 40 mg
tablets. How many tablets should the nurse administer?
0.5 tablet
Rationale:
o Step 1: Ordered dose: 20 mg.
o Step 2: Available dose: 40 mg per tablet.
o Step 3: Calculate tablets: 20 mg ÷ 40 mg/tablet = 0.5 tablet.
o Step 4: Round to the nearest tenth: 0.5 (already at tenth).
o Note: Ensure the tablet is scored for splitting.
4. A nurse is preparing to administer dexamethasone 3 mg PO every 12 hr. Available is
dexamethasone oral solution 0.5 mg/5 mL. How many mL should the nurse administer
per dose?
30 mL
Rationale:
o Step 1: Ordered dose: 3 mg.
, o Step 2: Available concentration: 0.5 mg/5 mL.
o Step 3: Calculate mL: (3 mg ÷ 0.5 mg) × 5 mL = 6 × 5 mL = 30 mL.
o No rounding needed as the result is a whole number.
5. A nurse is preparing to administer ribavirin 600 mg PO every 12 hr. Available is ribavirin
200 mg/tablet. How many tablets should the nurse administer per dose?
3 tablets
Rationale:
o Step 1: Ordered dose: 600 mg.
o Step 2: Available dose: 200 mg/tablet.
o Step 3: Calculate tablets: 600 mg ÷ 200 mg/tablet = 3 tablets.
o No rounding needed as the result is a whole number.
Section 2: Parenteral Medication Calculations (Questions 6–
10)
6. A nurse is preparing to administer cefazolin 250 mg IM. Available is cefazolin powder
500 mg vial, reconstituted with 2 mL sterile water to yield 225 mg/mL. How many mL
should the nurse administer? (Round to the nearest tenth.)
1.1 mL
Rationale:
o Step 1: Ordered dose: 250 mg.
o Step 2: Available concentration: 225 mg/mL.
o Step 3: Calculate mL: 250 mg ÷ 225 mg/mL = 1.111 mL.
o Step 4: Round to the nearest tenth: 1.111 ≈ 1.1 mL.
7. A nurse is preparing to administer fentanyl 50 mcg IM. Available is fentanyl injection
0.05 mg/mL. How many mL should the nurse administer? (Round to the nearest whole
number.)
1 mL
Rationale:
o Step 1: Ordered dose: 50 mcg = 0.05 mg (since 1 mg = 1,000 mcg).
o Step 2: Available concentration: 0.05 mg/mL.
o Step 3: Calculate mL: 0.05 mg ÷ 0.05 mg/mL = 1 mL.
o No rounding needed as the result is a whole number.
8. A nurse is preparing to administer enoxaparin 30 mg subcutaneous. Available is
enoxaparin injection 60 mg/0.6 mL. How many mL should the nurse administer?
0.3 mL
Rationale:
o Step 1: Ordered dose: 30 mg.
o Step 2: Available concentration: 60 mg/0.6 mL = 100 mg/mL (60 ÷ 0.6 = 100).
o Step 3: Calculate mL: 30 mg ÷ 100 mg/mL = 0.3 mL.
o No rounding needed as the result is exact.
9. A nurse is preparing to administer hydralazine 0.2 mg/kg IM to a client who weighs 84
lb. Available is hydralazine 20 mg/mL. How many mL should the nurse administer?
