NURS130 Dosage Calculation for Nurses Practice Exam Study Guide Updated 2026
| Verified Questions and Answers with Detailed Rationales | Medication
Dosage Calculations, Unit Conversions (mg, g, mL), IV Flow Rate Calculations, Drip
Rate and Infusion Calculations, Pediatric and Adult Dosage, Safe Medication
Administration, Dimensional Analysis Method, Ratio and Proportion Method, Drug
Label Interpretation, NCLEX-Style Calculation Questions | Complete Exam Prep
Resource for Nursing Students Success
Question 1: A nurse is preparing to administer 500 mg of amoxicillin. The available
suspension is labeled 250 mg/5 mL. How many milliliters should the nurse
administer?
A. 5 mL
B. 7.5 mL
C. 10 mL
D. 12.5 mL
CORRECT ANSWER: C. 10 mL
Rationale: Using the formula: (Desired dose / Available dose) × Volume = (500 mg / 250
mg) × 5 mL = 2 × 5 mL = 10 mL.
Question 2: A patient is prescribed 0.25 mg of digoxin orally daily. The tablets
available are 0.125 mg each. How many tablets should the nurse give?
A. 0.5 tablet
B. 1 tablet
C. 1.5 tablets
D. 2 tablets
CORRECT ANSWER: D. 2 tablets
Rationale: Divide the prescribed dose by the available tablet strength: 0.25 mg ÷ 0.125
mg = 2 tablets.
Question 3: The physician orders 1,000 mL of normal saline to infuse over 8 hours.
The IV tubing delivers 15 gtt/mL. What is the flow rate in drops per minute?
A. 21 gtt/min
B. 31 gtt/min
C. 42 gtt/min
D. 63 gtt/min
CORRECT ANSWER: B. 31 gtt/min
Rationale: Total volume (1,000 mL) × drop factor (15 gtt/mL) ÷ total minutes (8 × 60 =
480 min) = 15,000 ÷ 480 ≈ 31.25 → rounded to 31 gtt/min.
Question 4: A child weighing 22 kg is prescribed acetaminophen at a dose of 15
mg/kg every 6 hours. How many milligrams should the child receive per dose?
,A. 150 mg
B. 220 mg
C. 330 mg
D. 450 mg
CORRECT ANSWER: C. 330 mg
Rationale: Multiply weight by dose per kg: 22 kg × 15 mg/kg = 330 mg.
Question 5: A heparin infusion is ordered at 18 units/kg/hour for a patient weighing
70 kg. The heparin solution is 25,000 units in 500 mL D5W. What is the infusion rate
in mL/hour?
A. 18 mL/hr
B. 25.2 mL/hr
C. 30 mL/hr
D. 36 mL/hr
CORRECT ANSWER: B. 25.2 mL/hr
Rationale: Total dose per hour = 18 units/kg/hr × 70 kg = 1,260 units/hr. Concentration =
25,000 units / 500 mL = 50 units/mL. Infusion rate = 1,260 ÷ 50 = 25.2 mL/hr.
Question 6: A nurse needs to administer 60 mEq of potassium chloride IV. The
available vial contains 40 mEq/20 mL. How many milliliters should be given?
A. 15 mL
B. 20 mL
C. 30 mL
D. 40 mL
CORRECT ANSWER: C. 30 mL
Rationale: (60 mEq / 40 mEq) × 20 mL = 1.5 × 20 = 30 mL.
Question 7: An order reads: “Administer furosemide 40 mg IV push now.” The
available vial is labeled 10 mg/mL. How many milliliters will the nurse draw up?
A. 2 mL
B. 4 mL
C. 6 mL
D. 8 mL
CORRECT ANSWER: B. 4 mL
Rationale: 40 mg ÷ 10 mg/mL = 4 mL.
Question 8: A patient is to receive 250 mL of IV fluid over 2 hours using microdrip
tubing (60 gtt/mL). What is the correct drip rate?
A. 60 gtt/min
B. 75 gtt/min
,C. 100 gtt/min
D. 125 gtt/min
CORRECT ANSWER: D. 125 gtt/min
Rationale: (250 mL × 60 gtt/mL) ÷ (2 × 60 min) = 15,000 ÷ 120 = 125 gtt/min.
Question 9: A medication order is for 0.6 mg of atropine IV. The available
concentration is 0.4 mg/mL. How many milliliters should the nurse administer?
A. 0.5 mL
B. 1.0 mL
C. 1.5 mL
D. 2.0 mL
CORRECT ANSWER: C. 1.5 mL
Rationale: 0.6 mg ÷ 0.4 mg/mL = 1.5 mL.
Question 10: A patient is prescribed 7.5 mg of warfarin orally. The available tablets
are 2.5 mg each. How many tablets should be administered?
A. 2 tablets
B. 3 tablets
C. 4 tablets
D. 5 tablets
CORRECT ANSWER: B. 3 tablets
Rationale: 7.5 mg ÷ 2.5 mg = 3 tablets.
Question 11: The provider orders an IV bolus of 500 mL normal saline over 30
minutes. What is the infusion rate in mL/hour?
A. 500 mL/hr
B. 750 mL/hr
C. 1,000 mL/hr
D. 1,200 mL/hr
CORRECT ANSWER: C. 1,000 mL/hr
Rationale: Convert 30 minutes to 0.5 hours. Rate = 500 mL ÷ 0.5 hr = 1,000 mL/hr.
Question 12: A patient is to receive 1.5 g of cefazolin IV. The reconstituted vial
contains 500 mg/mL. How many milliliters should the nurse administer?
A. 2 mL
B. 3 mL
C. 4 mL
D. 5 mL
CORRECT ANSWER: B. 3 mL
, Rationale: Convert 1.5 g = 1,500 mg. 1,500 mg ÷ 500 mg/mL = 3 mL.
Question 13: A pediatric patient weighing 16 kg is prescribed ibuprofen at 10
mg/kg/dose. The oral suspension is 100 mg/5 mL. How many milliliters should be
given per dose?
A. 4 mL
B. 6 mL
C. 8 mL
D. 10 mL
CORRECT ANSWER: C. 8 mL
Rationale: Dose = 16 kg × 10 mg/kg = 160 mg. Volume = (160 mg / 100 mg) × 5 mL = 1.6 ×
5 = 8 mL.
Question 14: A dopamine infusion is ordered at 5 mcg/kg/min for a patient weighing
80 kg. The solution is 400 mg in 250 mL D5W. What is the infusion rate in mL/hour?
A. 10 mL/hr
B. 15 mL/hr
C. 20 mL/hr
D. 25 mL/hr
CORRECT ANSWER: B. 15 mL/hr
Rationale: Total dose/min = 5 mcg/kg/min × 80 kg = 400 mcg/min. Convert to mcg/hr:
400 × 60 = 24,000 mcg/hr. Concentration = 400,000 mcg / 250 mL = 1,600 mcg/mL. Rate
= 24,000 ÷ 1,600 = 15 mL/hr.
Question 15: A nurse is to administer 2.5 mg of haloperidol IM. The available vial is
5 mg/mL. How many milliliters should be drawn up?
A. 0.25 mL
B. 0.5 mL
C. 1.0 mL
D. 1.5 mL
CORRECT ANSWER: B. 0.5 mL
Rationale: 2.5 mg ÷ 5 mg/mL = 0.5 mL.
Question 16: An IV order is for 1 L of D5NS to infuse over 10 hours. What is the flow
rate in mL/hour?
A. 80 mL/hr
B. 100 mL/hr
C. 120 mL/hr
D. 150 mL/hr
CORRECT ANSWER: B. 100 mL/hr
| Verified Questions and Answers with Detailed Rationales | Medication
Dosage Calculations, Unit Conversions (mg, g, mL), IV Flow Rate Calculations, Drip
Rate and Infusion Calculations, Pediatric and Adult Dosage, Safe Medication
Administration, Dimensional Analysis Method, Ratio and Proportion Method, Drug
Label Interpretation, NCLEX-Style Calculation Questions | Complete Exam Prep
Resource for Nursing Students Success
Question 1: A nurse is preparing to administer 500 mg of amoxicillin. The available
suspension is labeled 250 mg/5 mL. How many milliliters should the nurse
administer?
A. 5 mL
B. 7.5 mL
C. 10 mL
D. 12.5 mL
CORRECT ANSWER: C. 10 mL
Rationale: Using the formula: (Desired dose / Available dose) × Volume = (500 mg / 250
mg) × 5 mL = 2 × 5 mL = 10 mL.
Question 2: A patient is prescribed 0.25 mg of digoxin orally daily. The tablets
available are 0.125 mg each. How many tablets should the nurse give?
A. 0.5 tablet
B. 1 tablet
C. 1.5 tablets
D. 2 tablets
CORRECT ANSWER: D. 2 tablets
Rationale: Divide the prescribed dose by the available tablet strength: 0.25 mg ÷ 0.125
mg = 2 tablets.
Question 3: The physician orders 1,000 mL of normal saline to infuse over 8 hours.
The IV tubing delivers 15 gtt/mL. What is the flow rate in drops per minute?
A. 21 gtt/min
B. 31 gtt/min
C. 42 gtt/min
D. 63 gtt/min
CORRECT ANSWER: B. 31 gtt/min
Rationale: Total volume (1,000 mL) × drop factor (15 gtt/mL) ÷ total minutes (8 × 60 =
480 min) = 15,000 ÷ 480 ≈ 31.25 → rounded to 31 gtt/min.
Question 4: A child weighing 22 kg is prescribed acetaminophen at a dose of 15
mg/kg every 6 hours. How many milligrams should the child receive per dose?
,A. 150 mg
B. 220 mg
C. 330 mg
D. 450 mg
CORRECT ANSWER: C. 330 mg
Rationale: Multiply weight by dose per kg: 22 kg × 15 mg/kg = 330 mg.
Question 5: A heparin infusion is ordered at 18 units/kg/hour for a patient weighing
70 kg. The heparin solution is 25,000 units in 500 mL D5W. What is the infusion rate
in mL/hour?
A. 18 mL/hr
B. 25.2 mL/hr
C. 30 mL/hr
D. 36 mL/hr
CORRECT ANSWER: B. 25.2 mL/hr
Rationale: Total dose per hour = 18 units/kg/hr × 70 kg = 1,260 units/hr. Concentration =
25,000 units / 500 mL = 50 units/mL. Infusion rate = 1,260 ÷ 50 = 25.2 mL/hr.
Question 6: A nurse needs to administer 60 mEq of potassium chloride IV. The
available vial contains 40 mEq/20 mL. How many milliliters should be given?
A. 15 mL
B. 20 mL
C. 30 mL
D. 40 mL
CORRECT ANSWER: C. 30 mL
Rationale: (60 mEq / 40 mEq) × 20 mL = 1.5 × 20 = 30 mL.
Question 7: An order reads: “Administer furosemide 40 mg IV push now.” The
available vial is labeled 10 mg/mL. How many milliliters will the nurse draw up?
A. 2 mL
B. 4 mL
C. 6 mL
D. 8 mL
CORRECT ANSWER: B. 4 mL
Rationale: 40 mg ÷ 10 mg/mL = 4 mL.
Question 8: A patient is to receive 250 mL of IV fluid over 2 hours using microdrip
tubing (60 gtt/mL). What is the correct drip rate?
A. 60 gtt/min
B. 75 gtt/min
,C. 100 gtt/min
D. 125 gtt/min
CORRECT ANSWER: D. 125 gtt/min
Rationale: (250 mL × 60 gtt/mL) ÷ (2 × 60 min) = 15,000 ÷ 120 = 125 gtt/min.
Question 9: A medication order is for 0.6 mg of atropine IV. The available
concentration is 0.4 mg/mL. How many milliliters should the nurse administer?
A. 0.5 mL
B. 1.0 mL
C. 1.5 mL
D. 2.0 mL
CORRECT ANSWER: C. 1.5 mL
Rationale: 0.6 mg ÷ 0.4 mg/mL = 1.5 mL.
Question 10: A patient is prescribed 7.5 mg of warfarin orally. The available tablets
are 2.5 mg each. How many tablets should be administered?
A. 2 tablets
B. 3 tablets
C. 4 tablets
D. 5 tablets
CORRECT ANSWER: B. 3 tablets
Rationale: 7.5 mg ÷ 2.5 mg = 3 tablets.
Question 11: The provider orders an IV bolus of 500 mL normal saline over 30
minutes. What is the infusion rate in mL/hour?
A. 500 mL/hr
B. 750 mL/hr
C. 1,000 mL/hr
D. 1,200 mL/hr
CORRECT ANSWER: C. 1,000 mL/hr
Rationale: Convert 30 minutes to 0.5 hours. Rate = 500 mL ÷ 0.5 hr = 1,000 mL/hr.
Question 12: A patient is to receive 1.5 g of cefazolin IV. The reconstituted vial
contains 500 mg/mL. How many milliliters should the nurse administer?
A. 2 mL
B. 3 mL
C. 4 mL
D. 5 mL
CORRECT ANSWER: B. 3 mL
, Rationale: Convert 1.5 g = 1,500 mg. 1,500 mg ÷ 500 mg/mL = 3 mL.
Question 13: A pediatric patient weighing 16 kg is prescribed ibuprofen at 10
mg/kg/dose. The oral suspension is 100 mg/5 mL. How many milliliters should be
given per dose?
A. 4 mL
B. 6 mL
C. 8 mL
D. 10 mL
CORRECT ANSWER: C. 8 mL
Rationale: Dose = 16 kg × 10 mg/kg = 160 mg. Volume = (160 mg / 100 mg) × 5 mL = 1.6 ×
5 = 8 mL.
Question 14: A dopamine infusion is ordered at 5 mcg/kg/min for a patient weighing
80 kg. The solution is 400 mg in 250 mL D5W. What is the infusion rate in mL/hour?
A. 10 mL/hr
B. 15 mL/hr
C. 20 mL/hr
D. 25 mL/hr
CORRECT ANSWER: B. 15 mL/hr
Rationale: Total dose/min = 5 mcg/kg/min × 80 kg = 400 mcg/min. Convert to mcg/hr:
400 × 60 = 24,000 mcg/hr. Concentration = 400,000 mcg / 250 mL = 1,600 mcg/mL. Rate
= 24,000 ÷ 1,600 = 15 mL/hr.
Question 15: A nurse is to administer 2.5 mg of haloperidol IM. The available vial is
5 mg/mL. How many milliliters should be drawn up?
A. 0.25 mL
B. 0.5 mL
C. 1.0 mL
D. 1.5 mL
CORRECT ANSWER: B. 0.5 mL
Rationale: 2.5 mg ÷ 5 mg/mL = 0.5 mL.
Question 16: An IV order is for 1 L of D5NS to infuse over 10 hours. What is the flow
rate in mL/hour?
A. 80 mL/hr
B. 100 mL/hr
C. 120 mL/hr
D. 150 mL/hr
CORRECT ANSWER: B. 100 mL/hr
