Dosage Calculation Quiz

Twenty drug calculation questions, from counting tablets to microgram-per-kilo infusions. Have a pen ready. The key formula: what you want ÷ what you’ve got × the volume it comes in. Tap an answer to see if you’re right.

  1. Question 1 of 20

    Ordered: paracetamol 1 g. Stock: 500 mg tablets. How many tablets?

    1. 0.5
    2. 1
    3. 4
    4. 2
    Show answer

    Answer: 2. 1 g = 1,000 mg. 1,000 ÷ 500 = 2 tablets.

  2. Question 2 of 20

    How many milligrams is 0.5 g?

    1. 5,000 mg
    2. 500 mg
    3. 5 mg
    4. 50 mg
    Show answer

    Answer: 500 mg. Multiply grams by 1,000 to get milligrams.

  3. Question 3 of 20

    How many micrograms are in 1 mg?

    1. 100
    2. 10
    3. 1,000
    4. 1,000,000
    Show answer

    Answer: 1,000. g → mg → microgram: each step is × 1,000.

  4. Question 4 of 20

    Ordered: 25 mg. Stock: 12.5 mg tablets. How many tablets?

    1. 2
    2. 4
    3. 1.5
    4. 0.5
    Show answer

    Answer: 2. 25 ÷ 12.5 = 2.

  5. Question 5 of 20

    Ordered: metoprolol 25 mg. Stock: 50 mg tablets. How many tablets?

    1. 1 tablet
    2. A quarter of a tablet
    3. Half a tablet
    4. 2 tablets
    Show answer

    Answer: Half a tablet. 25 ÷ 50 = 0.5. Only halve tablets that are scored and safe to split.

  6. Question 6 of 20

    Ordered: amoxicillin 250 mg. Stock: 250 mg/5 mL. How many mL?

    1. 2.5 mL
    2. 5 mL
    3. 1 mL
    4. 10 mL
    Show answer

    Answer: 5 mL. 250 ÷ 250 × 5 = 5 mL.

  7. Question 7 of 20

    Ordered: 75 mg. Stock: 50 mg/mL. How many mL?

    1. 2.5 mL
    2. 0.67 mL
    3. 15 mL
    4. 1.5 mL
    Show answer

    Answer: 1.5 mL. 75 ÷ 50 × 1 = 1.5 mL.

  8. Question 8 of 20

    Ordered: amoxicillin 400 mg. Stock: 250 mg/5 mL. How many mL?

    1. 8 mL
    2. 3.1 mL
    3. 6.25 mL
    4. 10 mL
    Show answer

    Answer: 8 mL. 400 ÷ 250 × 5 = 8 mL.

  9. Question 9 of 20

    Ordered: gentamicin 80 mg. Stock: 80 mg/2 mL. How many mL?

    1. 4 mL
    2. 0.5 mL
    3. 2 mL
    4. 1 mL
    Show answer

    Answer: 2 mL. 80 ÷ 80 × 2 = 2 mL.

  10. Question 10 of 20

    Ordered: morphine 2 mg IV. Stock: 10 mg/mL. How many mL?

    1. 2 mL
    2. 0.2 mL
    3. 0.5 mL
    4. 5 mL
    Show answer

    Answer: 0.2 mL. 2 ÷ 10 × 1 = 0.2 mL. Small volumes are where decimal slips happen.

  11. Question 11 of 20

    A 20 kg child needs paracetamol 15 mg/kg. What dose?

    1. 200 mg
    2. 150 mg
    3. 750 mg
    4. 300 mg
    Show answer

    Answer: 300 mg. 15 × 20 = 300 mg.

  12. Question 12 of 20

    That 300 mg dose comes as a 120 mg/5 mL liquid. How many mL?

    1. 12.5 mL
    2. 10 mL
    3. 15 mL
    4. 7.5 mL
    Show answer

    Answer: 12.5 mL. 300 ÷ 120 × 5 = 12.5 mL.

  13. Question 13 of 20

    1,000 mL of fluid is to run over 8 hours. What pump rate?

    1. 200 mL/h
    2. 125 mL/h
    3. 80 mL/h
    4. 100 mL/h
    Show answer

    Answer: 125 mL/h. 1,000 ÷ 8 = 125 mL an hour.

  14. Question 14 of 20

    250 mL is to run over 30 minutes. What pump rate in mL/h?

    1. 500 mL/h
    2. 125 mL/h
    3. 750 mL/h
    4. 250 mL/h
    Show answer

    Answer: 500 mL/h. Rates are per hour: 250 mL in half an hour = 500 mL in an hour.

  15. Question 15 of 20

    1,000 mL over 8 hours through a giving set of 20 drops/mL. Roughly how many drops a minute?

    1. 21
    2. 60
    3. 42
    4. 125
    Show answer

    Answer: 42. 1,000 × 20 = 20,000 drops ÷ 480 minutes ≈ 41.7, so 42 drops a minute.

  16. Question 16 of 20

    How many mg of adrenaline are in 1 mL of a 1:1,000 solution?

    1. 10 mg
    2. 0.1 mg
    3. 0.01 mg
    4. 1 mg
    Show answer

    Answer: 1 mg. 1:1,000 means 1 g in 1,000 mL, which is 1 mg/mL. 1:10,000 is 0.1 mg/mL.

  17. Question 17 of 20

    How many grams of glucose are in 1 litre of 5% glucose?

    1. 500 g
    2. 0.5 g
    3. 5 g
    4. 50 g
    Show answer

    Answer: 50 g. Percent here means grams per 100 mL: 5 g per 100 mL, so 50 g per litre.

  18. Question 18 of 20

    Heparin: 25,000 units in 50 mL. Ordered: 1,000 units an hour. What rate?

    1. 4 mL/h
    2. 2 mL/h
    3. 1 mL/h
    4. 20 mL/h
    Show answer

    Answer: 2 mL/h. 25,000 ÷ 50 = 500 units/mL. 1,000 ÷ 500 = 2 mL an hour.

  19. Question 19 of 20

    If the maximum dose of lidocaine is 3 mg/kg, how many mL of 1% lidocaine is that for a 70 kg adult?

    1. 21 mL
    2. 7 mL
    3. 2.1 mL
    4. 210 mL
    Show answer

    Answer: 21 mL. 1% = 10 mg/mL. 3 × 70 = 210 mg. 210 ÷ 10 = 21 mL.

  20. Question 20 of 20

    Ordered: 5 microgram/kg/min for a 70 kg patient. Stock: 200 mg in 50 mL. What pump rate?

    1. 21 mL/h
    2. 0.875 mL/h
    3. 5.25 mL/h
    4. 52.5 mL/h
    Show answer

    Answer: 5.25 mL/h. 5 × 70 = 350 microgram/min × 60 = 21,000 microgram/h. 200 mg/50 mL = 4,000 microgram/mL. 21,000 ÷ 4,000 = 5.25 mL/h.

Practice only. These are made-up orders for learning. In real life, always double-check calculations and follow local policy.

Common questions

What is the formula for drug calculations?

Volume = (dose wanted ÷ dose in stock) × stock volume. Put everything in the same units first (g, mg or micrograms).

How do you calculate an IV rate?

Pump rate (mL/h) = volume ÷ time in hours. For a gravity drip: drops per minute = volume (mL) × drop factor (drops/mL) ÷ time in minutes.

How do I avoid calculation errors?

Convert units first, estimate the answer before calculating, write a leading zero (0.5, not .5), never a trailing zero (5, not 5.0), and get an independent double-check for high-risk drugs.

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Updated 16 November 2026. General education, not medical advice. General education, not personal medical advice.