DOSAGE CALCULATIONS RN ATI ADULT
MEDICAL SURGICAL PROCTORED
ASSESSMENT 3 & 3.1 | PRACTICE QUESTIONS,
DETAILED VERIFIED ANSWERS &
RATIONALES | GRADED A+
• This practice set contains 200 rigorous dosage calculation and adult med-surg
questions mirroring the ATI RN Proctored Assessment 3 & 3.1 format, complete
with verified answers and detailed EXPERT RATIONALE.
• Work through each question independently before checking the highlighted
correct answer and EXPERT RATIONALE below it — this active recall method
maximizes retention and exam readiness.
DOSAGE CALCULATIONS — RN ATI ADULT MEDICAL SURGICAL PROCTORED
ASSESSMENT 3 & 3.1 | 200 PRACTICE QUESTIONS
1. A nurse is preparing to administer amoxicillin 500 mg PO. The medication is
available as 250 mg/5 mL. How many mL should the nurse administer?
A. 5 mL
B. 7.5 mL
C. 10 mL
D. 12.5 mL
E. 15 mL
CORRECT ANSWER: C. 10 mL
EXPERT RATIONALE: Use the formula: Desired/Have × Volume = 500/250 × 5 = 10 mL.
2. A nurse is to administer heparin 5,000 units subcutaneously. The vial reads
10,000 units/mL. How many mL should be administered?
,A. 1 mL
B. 0.25 mL
C. 0.75 mL
D. 2 mL
E. 0.5 mL
CORRECT ANSWER: E. 0.5 mL
EXPERT RATIONALE: 5,000/10,000 × 1 mL = 0.5 mL.
3. A client is ordered IV fluids at 125 mL/hr. The drop factor is 20 gtt/mL. What
is the flow rate in gtt/min?
A. 25 gtt/min
B. 30 gtt/min
C. 42 gtt/min
D. 50 gtt/min
E. 62 gtt/min
CORRECT ANSWER: C. 42 gtt/min
EXPERT RATIONALE: 125 mL/hr × 20 gtt/mL ÷ 60 min = 41.6 ≈ 42 gtt/min.
4. A physician orders morphine sulfate 4 mg IV. The available solution is 10
mg/mL. How many mL should the nurse administer?
A. 0.8 mL
B. 0.2 mL
C. 0.4 mL
D. 1 mL
E. 0.6 mL
, CORRECT ANSWER: C. 0.4 mL
EXPERT RATIONALE: 4/10 × 1 = 0.4 mL.
5. A nurse is administering vancomycin 1,000 mg in 250 mL NS over 90
minutes. What is the infusion rate in mL/hr?
A. 125 mL/hr
B. 150 mL/hr
C. 167 mL/hr
D. 200 mL/hr
E. 250 mL/hr
CORRECT ANSWER: C. 167 mL/hr
EXPERT RATIONALE: 250 mL ÷ 90 min × 60 = 166.6 ≈ 167 mL/hr.
6. A client weighing 70 kg is ordered dopamine at 5 mcg/kg/min. The solution
contains 400 mg/250 mL. What is the infusion rate in mL/hr?
A. 10.5 mL/hr
B. 13.1 mL/hr
C. 15.2 mL/hr
D. 17.8 mL/hr
E. 21 mL/hr
CORRECT ANSWER: B. 13.1 mL/hr
EXPERT RATIONALE: Concentration = 400 mg/250 mL = 1.6 mg/mL = 1,600 mcg/mL.
Dose = 5 × 70 = 350 mcg/min × 60 = 21,000 mcg/hr. Rate = 21,000 ÷ 1,600 = 13.1 mL/hr.
, 7. A nurse is to give penicillin V potassium 500 mg. Available: 125 mg/5 mL.
How many mL?
A. 10 mL
B. 15 mL
C. 20 mL
D. 25 mL
E. 30 mL
CORRECT ANSWER: C. 20 mL
EXPERT RATIONALE: 500/125 × 5 = 20 mL.
8. An order reads: regular insulin 18 units subcutaneous. The insulin is U-100.
Using a U-100 syringe, how many units should be drawn?
A. 10 units
B. 14 units
C. 18 units
D. 20 units
E. 22 units
CORRECT ANSWER: C. 18 units
EXPERT RATIONALE: On a U-100 syringe, 1 unit = 1 unit marking. Draw to the 18-unit
mark.
9. Ordered: Lasix 80 mg IV. Available: 10 mg/mL. How many mL?
A. 4 mL
B. 6 mL
C. 8 mL
MEDICAL SURGICAL PROCTORED
ASSESSMENT 3 & 3.1 | PRACTICE QUESTIONS,
DETAILED VERIFIED ANSWERS &
RATIONALES | GRADED A+
• This practice set contains 200 rigorous dosage calculation and adult med-surg
questions mirroring the ATI RN Proctored Assessment 3 & 3.1 format, complete
with verified answers and detailed EXPERT RATIONALE.
• Work through each question independently before checking the highlighted
correct answer and EXPERT RATIONALE below it — this active recall method
maximizes retention and exam readiness.
DOSAGE CALCULATIONS — RN ATI ADULT MEDICAL SURGICAL PROCTORED
ASSESSMENT 3 & 3.1 | 200 PRACTICE QUESTIONS
1. A nurse is preparing to administer amoxicillin 500 mg PO. The medication is
available as 250 mg/5 mL. How many mL should the nurse administer?
A. 5 mL
B. 7.5 mL
C. 10 mL
D. 12.5 mL
E. 15 mL
CORRECT ANSWER: C. 10 mL
EXPERT RATIONALE: Use the formula: Desired/Have × Volume = 500/250 × 5 = 10 mL.
2. A nurse is to administer heparin 5,000 units subcutaneously. The vial reads
10,000 units/mL. How many mL should be administered?
,A. 1 mL
B. 0.25 mL
C. 0.75 mL
D. 2 mL
E. 0.5 mL
CORRECT ANSWER: E. 0.5 mL
EXPERT RATIONALE: 5,000/10,000 × 1 mL = 0.5 mL.
3. A client is ordered IV fluids at 125 mL/hr. The drop factor is 20 gtt/mL. What
is the flow rate in gtt/min?
A. 25 gtt/min
B. 30 gtt/min
C. 42 gtt/min
D. 50 gtt/min
E. 62 gtt/min
CORRECT ANSWER: C. 42 gtt/min
EXPERT RATIONALE: 125 mL/hr × 20 gtt/mL ÷ 60 min = 41.6 ≈ 42 gtt/min.
4. A physician orders morphine sulfate 4 mg IV. The available solution is 10
mg/mL. How many mL should the nurse administer?
A. 0.8 mL
B. 0.2 mL
C. 0.4 mL
D. 1 mL
E. 0.6 mL
, CORRECT ANSWER: C. 0.4 mL
EXPERT RATIONALE: 4/10 × 1 = 0.4 mL.
5. A nurse is administering vancomycin 1,000 mg in 250 mL NS over 90
minutes. What is the infusion rate in mL/hr?
A. 125 mL/hr
B. 150 mL/hr
C. 167 mL/hr
D. 200 mL/hr
E. 250 mL/hr
CORRECT ANSWER: C. 167 mL/hr
EXPERT RATIONALE: 250 mL ÷ 90 min × 60 = 166.6 ≈ 167 mL/hr.
6. A client weighing 70 kg is ordered dopamine at 5 mcg/kg/min. The solution
contains 400 mg/250 mL. What is the infusion rate in mL/hr?
A. 10.5 mL/hr
B. 13.1 mL/hr
C. 15.2 mL/hr
D. 17.8 mL/hr
E. 21 mL/hr
CORRECT ANSWER: B. 13.1 mL/hr
EXPERT RATIONALE: Concentration = 400 mg/250 mL = 1.6 mg/mL = 1,600 mcg/mL.
Dose = 5 × 70 = 350 mcg/min × 60 = 21,000 mcg/hr. Rate = 21,000 ÷ 1,600 = 13.1 mL/hr.
, 7. A nurse is to give penicillin V potassium 500 mg. Available: 125 mg/5 mL.
How many mL?
A. 10 mL
B. 15 mL
C. 20 mL
D. 25 mL
E. 30 mL
CORRECT ANSWER: C. 20 mL
EXPERT RATIONALE: 500/125 × 5 = 20 mL.
8. An order reads: regular insulin 18 units subcutaneous. The insulin is U-100.
Using a U-100 syringe, how many units should be drawn?
A. 10 units
B. 14 units
C. 18 units
D. 20 units
E. 22 units
CORRECT ANSWER: C. 18 units
EXPERT RATIONALE: On a U-100 syringe, 1 unit = 1 unit marking. Draw to the 18-unit
mark.
9. Ordered: Lasix 80 mg IV. Available: 10 mg/mL. How many mL?
A. 4 mL
B. 6 mL
C. 8 mL
