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Dosage Calculations Mastery: Comprehensive 150-
Question Practice Examination with Evidence-Based
Rationales for Nursing and Healthcare Professionals
SECTION 1: BASIC CONVERSIONS AND CALCULATIONS (Questions 1-15)
1. A nurse is converting a medication order from grams to milligrams. The order is for 0.25
grams. How many milligrams should the nurse administer?
A. 2.5 mg
B. 25 mg
C. 250 mg
D. 2500 mg
CorreCt Answer: C
Rationale: To convert grams to milligrams, multiply by 1000. 0.25 g × 1000 = 250 mg. This is a
fundamental conversion used frequently in medication administration. Always double-check
decimal placement to prevent tenfold errors.
2. A medication order is written for 1.5 liters of IV fluid. How many milliliters is this equivalent
to?
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A. 15 mL
B. 150 mL
C. 1500 mL
D. 15,000 mL
CorreCt Answer: C
Rationale: To convert liters to milliliters, multiply by 1000. 1.5 L × 1000 = 1500 mL. This
conversion is essential when calculating IV infusion rates and fluid balance.
3. A nurse needs to convert 4.2 kilograms to pounds. Which of the following is the correct
conversion?
A. 8.4 lbs
B. 9.24 lbs
C. 9.8 lbs
D. 10.6 lbs
CorreCt Answer: B
Rationale: To convert kilograms to pounds, multiply by 2.2. 4.2 kg × 2.2 = 9.24 lbs.
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Weight conversion is critical for weight-based medication dosing.
4. A medication is available in a concentration of 500 mg/2 mL. How many milligrams are in 5
mL of this solution?
A. 1000 mg
B. 1250 mg
C. 1500 mg
D. 2000 mg
CorreCt Answer: B
Rationale: Set up a proportion: 500 mg / 2 mL = x mg / 5 mL. Cross-multiply: 2x = 2500. x = 1250
mg. This demonstrates the concept of concentration and ratio calculations.
5. A nurse needs to convert 150 pounds to kilograms. Which of the following is the
correct conversion? A. 68.2 kg
B. 70.5 kg
C. 72.7 kg
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D. 75.0 kg
CorreCt Answer: A
Rationale: To convert pounds to kilograms, divide by 2.2. 150 lbs ÷ 2.2 = 68.18 kg (rounded to
68.2 kg). This conversion is essential for weight-based dosing.
6. A medication order is written for 0.05 grams. How many micrograms is this equivalent to?
A. 50 mcg
B. 500 mcg
C. 5000 mcg
D. 50,000 mcg
CorreCt Answer: D
Rationale: First convert grams to milligrams: 0.05 g × 1000 = 50 mg. Then convert milligrams to
micrograms: 50 mg × 1000 = 50,000 mcg. This demonstrates multi-step conversion.
7. A nurse is preparing a medication that is available as 250 mg per 5 mL. The order is for 100
mg. How many milliliters should the nurse administer?
Dosage Calculations Mastery: Comprehensive 150-
Question Practice Examination with Evidence-Based
Rationales for Nursing and Healthcare Professionals
SECTION 1: BASIC CONVERSIONS AND CALCULATIONS (Questions 1-15)
1. A nurse is converting a medication order from grams to milligrams. The order is for 0.25
grams. How many milligrams should the nurse administer?
A. 2.5 mg
B. 25 mg
C. 250 mg
D. 2500 mg
CorreCt Answer: C
Rationale: To convert grams to milligrams, multiply by 1000. 0.25 g × 1000 = 250 mg. This is a
fundamental conversion used frequently in medication administration. Always double-check
decimal placement to prevent tenfold errors.
2. A medication order is written for 1.5 liters of IV fluid. How many milliliters is this equivalent
to?
, 2
A. 15 mL
B. 150 mL
C. 1500 mL
D. 15,000 mL
CorreCt Answer: C
Rationale: To convert liters to milliliters, multiply by 1000. 1.5 L × 1000 = 1500 mL. This
conversion is essential when calculating IV infusion rates and fluid balance.
3. A nurse needs to convert 4.2 kilograms to pounds. Which of the following is the correct
conversion?
A. 8.4 lbs
B. 9.24 lbs
C. 9.8 lbs
D. 10.6 lbs
CorreCt Answer: B
Rationale: To convert kilograms to pounds, multiply by 2.2. 4.2 kg × 2.2 = 9.24 lbs.
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Weight conversion is critical for weight-based medication dosing.
4. A medication is available in a concentration of 500 mg/2 mL. How many milligrams are in 5
mL of this solution?
A. 1000 mg
B. 1250 mg
C. 1500 mg
D. 2000 mg
CorreCt Answer: B
Rationale: Set up a proportion: 500 mg / 2 mL = x mg / 5 mL. Cross-multiply: 2x = 2500. x = 1250
mg. This demonstrates the concept of concentration and ratio calculations.
5. A nurse needs to convert 150 pounds to kilograms. Which of the following is the
correct conversion? A. 68.2 kg
B. 70.5 kg
C. 72.7 kg
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D. 75.0 kg
CorreCt Answer: A
Rationale: To convert pounds to kilograms, divide by 2.2. 150 lbs ÷ 2.2 = 68.18 kg (rounded to
68.2 kg). This conversion is essential for weight-based dosing.
6. A medication order is written for 0.05 grams. How many micrograms is this equivalent to?
A. 50 mcg
B. 500 mcg
C. 5000 mcg
D. 50,000 mcg
CorreCt Answer: D
Rationale: First convert grams to milligrams: 0.05 g × 1000 = 50 mg. Then convert milligrams to
micrograms: 50 mg × 1000 = 50,000 mcg. This demonstrates multi-step conversion.
7. A nurse is preparing a medication that is available as 250 mg per 5 mL. The order is for 100
mg. How many milliliters should the nurse administer?
