Drug Calculations & Q&A
1. Basic Conversions
Q1. How many milliliters (mL) are in 2 teaspoons?
A. 5 mL
B. 10 mL
C. 15 mL
D. 20 mL
Answer: B
Rationale: 1 teaspoon = 5 mL → 2 × 5 = 10 mL.
Q2. Convert 1 gram to milligrams.
A. 10 mg
B. 100 mg
C. 1000 mg
D. 10,000 mg
Answer: C
Rationale: 1 g = 1000 mg.
Q3. How many ounces are in 60 mL?
A. 1 oz
B. 2 oz
C. 3 oz
D. 4 oz
Answer: B
Rationale: 1 oz ≈ 30 mL → 60 ÷ 30 = 2 oz.
2. Dosage Calculations
Q4. A patient is prescribed 500 mg. Tablets are 250 mg each. How many tablets?
A. 1
B. 2
,C. 3
D. 4
Answer: B
Rationale: 500 ÷ 250 = 2 tablets.
Q5. Order: 750 mg. Stock: 250 mg tablets.
A. 1 tablet
B. 2 tablets
C. 3 tablets
D. 4 tablets
Answer: C
Rationale: 750 ÷ 250 = 3 tablets.
Q6. A child weighs 20 kg. Dose is 10 mg/kg. Total dose?
A. 100 mg
B. 150 mg
C. 200 mg
D. 250 mg
Answer: C
Rationale: 20 × 10 = 200 mg.
3. Weight-Based Calculations
Q7. Convert 70 kg to pounds. (1 kg = 2.2 lb)
A. 120 lb
B. 140 lb
C. 154 lb
D. 180 lb
Answer: C
Rationale: 70 × 2.2 = 154 lb.
Q8. Convert 176 lb to kg.
A. 70 kg
,B. 75 kg
C. 80 kg
D. 85 kg
Answer: C
Rationale: 176 ÷ 2.2 = 80 kg.
4. IV Flow Rate Calculations
Q9. IV order: 1000 mL over 8 hours. Drop factor: 15 gtt/mL. Flow rate?
A. 25 gtt/min
B. 30 gtt/min
C. 31 gtt/min
D. 40 gtt/min
Answer: C
Rationale:
(1000 × 15) ÷ (8 × 60) = 15000 ÷ 480 ≈ 31 gtt/min.
Q10. 500 mL over 5 hours, drop factor 20 gtt/mL.
A. 25 gtt/min
B. 33 gtt/min
C. 40 gtt/min
D. 50 gtt/min
Answer: C
Rationale: (500×20)/(300)=10000/300≈33? Wait check: 5 hrs=300 min → 10000/300≈33
gtt/min → closest C 40? Actually correct is ~33 gtt/min → best answer B not C.
Correct Answer: B
5. Alligation
Q11. Mix 10% and 40% solution to make 20%. Ratio?
A. 1:3
B. 2:1
C. 3:1
, D. 1:2
Answer: A
Rationale: Cross subtract:
40–20=20
20–10=10 → ratio 1:2? Wait correction: 20:10 simplifies to 2:1 → Answer B
6. Concentration Problems
Q12. 1 g in 100 mL = ? mg/mL
A. 5
B. 10
C. 15
D. 20
Answer: B
Rationale: 1000 mg ÷ 100 mL = 10 mg/mL.
Q13. 250 mg in 5 mL = ? mg/mL
A. 25
B. 50
C. 75
D. 100
Answer: B
Rationale: 250 ÷ 5 = 50 mg/mL.
6. Days Supply
Q14. 60 tablets, take 2 daily. Days supply?
A. 20
B. 30
C. 40
D. 60
Answer: B
Rationale: 60 ÷ 2 = 30 days.