Drug Dosage Calculation Questions for NORCET: 50 Practice Problems

Why Drug Dosage Calculation Questions Deserve Daily Practice

Dosage calculation questions follow a small set of repeating formulas. Once you know the formula, the only thing left to get wrong is the arithmetic, or a missed unit conversion. This is unlike a fact-recall question, where either you know the answer or you don't. Here, speed and accuracy come from repetition, not from reading a rule once and moving on.

Ten minutes of calculation practice, done daily, beats one long session done weekly. The goal isn't to memorise these 15 questions. It's to get fast enough at the underlying formulas that any new number, on exam day, doesn't slow you down.

Drug Dosage Calculation Questions:15 Practice Questions with Full Solutions

IV Flow Rate (mL/hr)

Q1. A patient is prescribed 1000 mL of Normal Saline to run over 8 hours. Using an infusion pump, what flow rate (mL/hr) should the nurse set?

A. 8000 mL/hr B. 133 mL/hr C. 100 mL/hr D. 125 mL/hr

Correct answer: D. 125 mL/hr
Solution: Flow rate = Total volume ÷ Time in hours = 1000 mL ÷ 8 hr = 125 mL/hr.

Q2. A patient needs 500 mL of Ringer's Lactate infused over 4 hours. Using an infusion pump, what flow rate (mL/hr) should the nurse set?

A. 83.3 mL/hr B. 2000 mL/hr C. 125 mL/hr D. 129 mL/hr

Correct answer: C. 125 mL/hr
Solution: Flow rate = Total volume ÷ Time in hours = 500 mL ÷ 4 hr = 125 mL/hr.

IV Drip Rate (gtt/min)

Q7. 1000 mL of IV fluid is to be infused over 8 hours using a set with a drop factor of 15 gtt/mL. What is the correct drip rate in drops per minute?

A. 16 gtt/min B. 62 gtt/min C. 31 gtt/min D. 125 gtt/min

Correct answer: C. 31 gtt/min
Solution: Drip rate = (Volume × Drop factor) ÷ Time in minutes = (1000 mL × 15 gtt/mL) ÷ 480 min = 31.2, rounded to 31 gtt/min.

Q9. 1000 mL of D5W is to run over 6 hours through a set calibrated at 10 gtt/mL. What is the correct drip rate?

A. 28 gtt/min B. 14 gtt/min C. 56 gtt/min D. 167 gtt/min

Correct answer: A. 28 gtt/min
Solution: Drip rate = (1000 mL × 10 gtt/mL) ÷ 360 min = 27.8, rounded to 28 gtt/min.

Weight-Based Dosage (mg/kg)

Q15. A child weighing 20 kg is prescribed a drug at 5 mg/kg/day. What is the total dose in mg?

A. 100 mg B. 4 mg C. 50 mg D. 120 mg

Correct answer: A. 100 mg
Solution: Total dose = Weight × Dose per kg = 20 kg × 5 mg/kg = 100 mg.

Q16. A 15 kg child is ordered an antibiotic at 8 mg/kg/dose. What is the total dose?

A. 60 mg B. 120 mg C. 135 mg D. 1.9 mg

Correct answer: B. 120 mg
Solution: Total dose = 15 kg × 8 mg/kg = 120 mg.

Dose Calculation from Stock

Q23. The doctor orders 500 mg of a drug. Available tablets are 250 mg each. How much should the nurse administer?

A. 0.5 tab B. 1 tab C. 3 tab D. 2 tab

Correct answer: D. 2 tab
Solution: Dose to give = (Desired ÷ Available) × Quantity = (500 ÷ 250) × 1 tab = 2 tablets.

Q26. 250 mg of an oral suspension is ordered. Available strength is 125 mg in 5 mL. How much should the nurse administer?

A. 2.5 mL B. 5 mL C. 10 mL D. 15 mL

Correct answer: C. 10 mL
Solution: Dose to give = (250 ÷ 125) × 5 mL = 10 mL.

Unit Conversion

Q31. A drug order reads 0.5 g. How many mg is this?

A. 50 mg B. 500 mg C. 50000 mg D. 5000 mg

Correct answer: B. 500 mg
Solution: 1 g = 1000 mg, so 0.5 g = 500 mg.

Q33. A patient's IV fluid order is written as 2.5 L. The nurse must record this on the intake chart in mL. How many mL is this?

A. 2500 mL B. 25000 mL C. 250 mL D. 250000 mL

Correct answer: A. 2500 mL
Solution: 1 L = 1000 mL, so 2.5 L = 2500 mL.

Percentage Solution / Dilution

Q37. How many grams of drug are present in 100 mL of a 2% solution?

A. 4 g B. 2 g C. 1 g D. 200 g

Correct answer: B. 2 g
Solution: Grams = (% ÷ 100) × Volume = (2 ÷ 100) × 100 = 2 g.

Q39. How many grams of drug are present in 500 mL of a 5% solution?

A. 50 g B. 25 g C. 2500 g D. 12.5 g

Correct answer: B. 25 g
Solution: Grams = (5 ÷ 100) × 500 = 25 g.

Paediatric Dosing (Clark's Rule)

Q41. Using Clark's Rule, calculate a child's dose if the adult dose is 500 mg and the child weighs 30 lb (average adult weight = 150 lb).

A. 50 mg B. 2500 mg C. 100 mg D. 200 mg

Correct answer: C. 100 mg
Solution: Child's dose = (Child's weight ÷ 150) × Adult dose = (30 ÷ 150) × 500 mg = 100 mg.

Weight-Based Infusion Rate (mcg/kg/min)

Q45. A 70 kg patient is ordered a Dopamine infusion at 5 mcg/kg/min. Available solution: 400 mg in 250 mL. What infusion rate (mL/hr) should be set?

A. 26.2 mL/hr B. 13.1 mL/hr C. 23.1 mL/hr D. 6.5 mL/hr

Correct answer: B. 13.1 mL/hr
Solution: Dose/min = 70 kg × 5 mcg/kg/min = 350 mcg/min. Concentration = (400 mg × 1000) ÷ 250 mL = 1600 mcg/mL. Rate = 350 ÷ 1600 = 0.219 mL/min = 13.1 mL/hr.

Q48. A 50 kg patient is ordered a Nitroglycerin infusion at 0.1 mcg/kg/min. Available solution: 50 mg in 250 mL. What infusion rate should be set?

A. 3 mL/hr B. 0.8 mL/hr C. 1.5 mL/hr D. 11.5 mL/hr

Correct answer: C. 1.5 mL/hr
Solution: Dose/min = 50 kg × 0.1 mcg/kg/min = 5 mcg/min. Concentration = (50 mg × 1000) ÷ 250 mL = 200 mcg/mL. Rate = 5 ÷ 200 = 0.025 mL/min = 1.5 mL/hr.

50 Drug Dosage Calculation Practice Problems with Solutions - Download PDF

These 15 cover the format. The full eBook has all 50 questions, arranged by calculation type, plus a complete answer key and full step-by-step working for every single question, so you can check not just what the right answer is, but exactly how to get there.

Download: NORCET 2026 Drug Dosage Calculation Questions

How to Practise Drug Dosage Calculation Daily

Attempt each question cold, without looking at the formula first. Write your working on paper, the same way you would in the exam. Only check the solution after you've committed to an answer. This is slower at first. It's also the only way calculation speed actually improves, because the exam won't give you a formula sheet either.