Chapter 1 —Medication Orders & Tablet
Calculations
1. Stem: A physician orders acetaminophen 0.5 g PO for an
adult patient. The medication on the unit is labeled 325
mg per tablet. How many tablets should the nurse
administer?
Options:
A. 1 tablet
B. 1½ tablets
C. 2 tablets
D. 3 tablets
Correct Answer: C. 2 tablets
Rationales:
, • Correct (C): 0.5 g = 500 mg. Tablets are 325 mg each.
Number tablets = 500 mg ÷ 325 mg = 1.538 → round to a
safe practical dose: give 2 tablets (650 mg) is a common
clinical choice when exact partial-tablet splitting is
impractical; if facility policy allows tablet splitting, nurse
would assess splitting to nearest half (1.5). Step
calculation: 500 ÷ 325 = 1.538.
• A (1 tablet): Reflects under-dosing by misreading g as mg
(thinking 0.5 means 0.5 mg) or truncating 1.538 to 1 —
common rounding-down error.
• B (1½ tablets): Reflects correct mathematical rounding to
nearest half (1.5) but assumes tablet can be safely halved
and that rounding to 1.5 is preferred — not always
allowable; also some nurses incorrectly choose 1.5 when
facility policy prefers whole tablets unless scored.
• D (3 tablets): Reflects mistaken conversion (e.g.,
calculating 3 × 325 = 975 mg then mis-associating with 0.5
g) or rounding up excessively.
Teaching Point: Always convert units first (g → mg), then
divide by tablet strength.
Chapter 1, Section 1.2 — Metric Conversions & Unit
Awareness
2. Chapter Reference: Chapter 1 — Section 1.2: Metric
Conversions & Unit Awareness
, Stem: Order: Amoxicillin 125 mg PO. Medication available:
250 mg per 5 mL suspension. How many milliliters should
be given?
Options:
A. 1.25 mL
B. 2.5 mL
C. 5 mL
D. 10 mL
Correct Answer: B. 2.5 mL
Rationales:
• Correct (B): Use proportion: 250 mg : 5 mL = 125 mg : x
mL. x = 125 × (5/250) = 125 × 0.02 = 2.5 mL.
• A (1.25 mL): Represents a decimal-place error (dividing by
2 twice) or miscalculation of the ratio (for example,
treating 125 as half of 250 then halving the volume again).
• C (5 mL): Reflects misreading the label and giving full vial
volume instead of proportional dose.
• D (10 mL): Reflects doubling the correct amount —
common when a nurse mistakenly doubles dose for safety.
Teaching Point: Set up ratios (D : H = X : V) and perform
unit conversion first.
Chapter 1, Section 1.3 — IV Infusion Rate (mL/hr)
3. Chapter Reference: Chapter 1 — Section 1.3: IV Infusion
Rate (mL/hr)
, Stem: The nurse must infuse 1,000 mL of normal saline
over 8 hours. What rate should be programmed on the
infusion pump (mL/hr)?
Options:
A. 100 mL/hr
B. 125 mL/hr
C. 150 mL/hr
D. 200 mL/hr
Correct Answer: B. 125 mL/hr
Rationales:
• Correct (B): Rate (mL/hr) = Total volume ÷ hours = 1,000
mL ÷ 8 hr = 125 mL/hr.
• A (100 mL/hr): Reflects dividing by 10 (1000 ÷ 10) instead
of by 8 — a common mental arithmetic slip.
• C (150 mL/hr): Reflects rounding up incorrectly (1,000 ÷
6.67 ≈150) or confusing hours.
• D (200 mL/hr): Reflects dividing by 5 (1000 ÷ 5), likely
misreading infusion time.
Teaching Point: Use total volume ÷ total hours; program
pump with mL/hr.
Chapter 1, Section 1.4 — Drop Factor Calculations (gtt/min)
4. Chapter Reference: Chapter 1 — Section 1.4: Drop Factor
Calculations (gtt/min)
Stem: Infuse 250 mL D5W over 2 hours using tubing with a
Calculations
1. Stem: A physician orders acetaminophen 0.5 g PO for an
adult patient. The medication on the unit is labeled 325
mg per tablet. How many tablets should the nurse
administer?
Options:
A. 1 tablet
B. 1½ tablets
C. 2 tablets
D. 3 tablets
Correct Answer: C. 2 tablets
Rationales:
, • Correct (C): 0.5 g = 500 mg. Tablets are 325 mg each.
Number tablets = 500 mg ÷ 325 mg = 1.538 → round to a
safe practical dose: give 2 tablets (650 mg) is a common
clinical choice when exact partial-tablet splitting is
impractical; if facility policy allows tablet splitting, nurse
would assess splitting to nearest half (1.5). Step
calculation: 500 ÷ 325 = 1.538.
• A (1 tablet): Reflects under-dosing by misreading g as mg
(thinking 0.5 means 0.5 mg) or truncating 1.538 to 1 —
common rounding-down error.
• B (1½ tablets): Reflects correct mathematical rounding to
nearest half (1.5) but assumes tablet can be safely halved
and that rounding to 1.5 is preferred — not always
allowable; also some nurses incorrectly choose 1.5 when
facility policy prefers whole tablets unless scored.
• D (3 tablets): Reflects mistaken conversion (e.g.,
calculating 3 × 325 = 975 mg then mis-associating with 0.5
g) or rounding up excessively.
Teaching Point: Always convert units first (g → mg), then
divide by tablet strength.
Chapter 1, Section 1.2 — Metric Conversions & Unit
Awareness
2. Chapter Reference: Chapter 1 — Section 1.2: Metric
Conversions & Unit Awareness
, Stem: Order: Amoxicillin 125 mg PO. Medication available:
250 mg per 5 mL suspension. How many milliliters should
be given?
Options:
A. 1.25 mL
B. 2.5 mL
C. 5 mL
D. 10 mL
Correct Answer: B. 2.5 mL
Rationales:
• Correct (B): Use proportion: 250 mg : 5 mL = 125 mg : x
mL. x = 125 × (5/250) = 125 × 0.02 = 2.5 mL.
• A (1.25 mL): Represents a decimal-place error (dividing by
2 twice) or miscalculation of the ratio (for example,
treating 125 as half of 250 then halving the volume again).
• C (5 mL): Reflects misreading the label and giving full vial
volume instead of proportional dose.
• D (10 mL): Reflects doubling the correct amount —
common when a nurse mistakenly doubles dose for safety.
Teaching Point: Set up ratios (D : H = X : V) and perform
unit conversion first.
Chapter 1, Section 1.3 — IV Infusion Rate (mL/hr)
3. Chapter Reference: Chapter 1 — Section 1.3: IV Infusion
Rate (mL/hr)
, Stem: The nurse must infuse 1,000 mL of normal saline
over 8 hours. What rate should be programmed on the
infusion pump (mL/hr)?
Options:
A. 100 mL/hr
B. 125 mL/hr
C. 150 mL/hr
D. 200 mL/hr
Correct Answer: B. 125 mL/hr
Rationales:
• Correct (B): Rate (mL/hr) = Total volume ÷ hours = 1,000
mL ÷ 8 hr = 125 mL/hr.
• A (100 mL/hr): Reflects dividing by 10 (1000 ÷ 10) instead
of by 8 — a common mental arithmetic slip.
• C (150 mL/hr): Reflects rounding up incorrectly (1,000 ÷
6.67 ≈150) or confusing hours.
• D (200 mL/hr): Reflects dividing by 5 (1000 ÷ 5), likely
misreading infusion time.
Teaching Point: Use total volume ÷ total hours; program
pump with mL/hr.
Chapter 1, Section 1.4 — Drop Factor Calculations (gtt/min)
4. Chapter Reference: Chapter 1 — Section 1.4: Drop Factor
Calculations (gtt/min)
Stem: Infuse 250 mL D5W over 2 hours using tubing with a
