Test Bank |
Henke's Med-Math: Dosage Calculation, Preparation & Administration, 10th
Edition — 1,200 Original Practice Questions with Answers & Teaching
Rationales
Aligned with the textbook by Susan Buchholz
Page 1
,Coverage
• Chapter 1: Arithmetic Needed for Dosage — 120 questions
• Chapter 2: Metric and Household Systems of Measurement — 120 questions
• Chapter 3: Drug Abbreviations, Labels, and Packaging — 240 questions
• Chapter 5: Liquids for Injection — 120 questions
• Chapter 6: Calculation of Basic IV Drip Rates — 120 questions
• Chapter 7: Special Types of IV Calculations — 120 questions
• Chapter 8: Dosage Problems for Infants and Children — 120 questions
• Chapter 9: Information Basic to Administering Drugs — 120 questions
• Chapter 10: Administration Procedures — 120 questions
Page 2
,Chapter 1: Arithmetic Needed for Dosage
1. What is 75% of 50?
A. -25
B. 42.5
C. 37.5
D. 3.75
Answer: C — 37.5
Rationale: Convert 75% to 0.75 and multiply by 50. 0.75 × 50 = 37.5. Percent means “per 100,” so
dividing the percent by 100 before multiplying prevents a tenfold or hundredfold error. Clinical
reasoning: first identify exactly what the stem is testing—such as drug class, mechanism, indication,
expected effect, adverse reaction, contraindication, monitoring priority, or patient teaching—then select
the option that answers that dimension most directly. Safety connection: the correct response links
pharmacology knowledge to prevention of medication error, recognition of toxicity or deterioration, and
appropriate follow-up. Why the distractors are incorrect: some alternatives may describe a different
property of the drug or class, while others conflict with the requested clinical priority or with safe
medication-use principles.
2. Calculate 1/2 - 1/2. Give the answer in simplest form.
A. 0
B. 3/4
C. 2/3
D. 1/2
Answer: A — 0
Rationale: Convert to compatible fractions or multiply numerators and denominators as required. The
exact result simplifies to 0; reducing the fraction removes common factors and gives the safest form for
later dosage work. Calculation reasoning: keep the units visible through the setup so incompatible units
are converted before arithmetic and the unwanted units cancel. Round only at the final step unless the
problem or institutional policy specifies otherwise, then perform a reasonableness check against the
ordered dose, available concentration, route, and clinical context. Why the distractors are incorrect:
alternative numeric choices commonly result from reversing desired and available quantities, omitting a
conversion, multiplying instead of dividing, using the wrong time unit, or rounding too early.
3. Calculate 1/4 + 1/2. Give the answer in simplest form.
A. 1/2
B. 2/3
C. 3/4
Page 3
, D. Alternative response 4
Answer: C — 3/4
Rationale: Convert to compatible fractions or multiply numerators and denominators as required. The
exact result simplifies to 3/4; reducing the fraction removes common factors and gives the safest form
for later dosage work. Calculation reasoning: keep the units visible through the setup so incompatible
units are converted before arithmetic and the unwanted units cancel. Round only at the final step unless
the problem or institutional policy specifies otherwise, then perform a reasonableness check against the
ordered dose, available concentration, route, and clinical context. Why the distractors are incorrect:
alternative numeric choices commonly result from reversing desired and available quantities, omitting a
conversion, multiplying instead of dividing, using the wrong time unit, or rounding too early.
4. What is 25% of 120?
A. 95
B. 3
C. 35
D. 30
Answer: D — 30
Rationale: Convert 25% to 0.25 and multiply by 120. 0.25 × 120 = 30. Percent means “per 100,” so
dividing the percent by 100 before multiplying prevents a tenfold or hundredfold error. Clinical
reasoning: first identify exactly what the stem is testing—such as drug class, mechanism, indication,
expected effect, adverse reaction, contraindication, monitoring priority, or patient teaching—then select
the option that answers that dimension most directly. Safety connection: the correct response links
pharmacology knowledge to prevention of medication error, recognition of toxicity or deterioration, and
appropriate follow-up. Why the distractors are incorrect: some alternatives may describe a different
property of the drug or class, while others conflict with the requested clinical priority or with safe
medication-use principles.
5. Calculate 1/3 + 1/8. Give the answer in simplest form.
A. 3/4
B. 11/24
C. 2/3
D. 1/2
Answer: B — 11/24
Rationale: Convert to compatible fractions or multiply numerators and denominators as required. The
exact result simplifies to 11/24; reducing the fraction removes common factors and gives the safest form
for later dosage work. Calculation reasoning: keep the units visible through the setup so incompatible
Page 4
Henke's Med-Math: Dosage Calculation, Preparation & Administration, 10th
Edition — 1,200 Original Practice Questions with Answers & Teaching
Rationales
Aligned with the textbook by Susan Buchholz
Page 1
,Coverage
• Chapter 1: Arithmetic Needed for Dosage — 120 questions
• Chapter 2: Metric and Household Systems of Measurement — 120 questions
• Chapter 3: Drug Abbreviations, Labels, and Packaging — 240 questions
• Chapter 5: Liquids for Injection — 120 questions
• Chapter 6: Calculation of Basic IV Drip Rates — 120 questions
• Chapter 7: Special Types of IV Calculations — 120 questions
• Chapter 8: Dosage Problems for Infants and Children — 120 questions
• Chapter 9: Information Basic to Administering Drugs — 120 questions
• Chapter 10: Administration Procedures — 120 questions
Page 2
,Chapter 1: Arithmetic Needed for Dosage
1. What is 75% of 50?
A. -25
B. 42.5
C. 37.5
D. 3.75
Answer: C — 37.5
Rationale: Convert 75% to 0.75 and multiply by 50. 0.75 × 50 = 37.5. Percent means “per 100,” so
dividing the percent by 100 before multiplying prevents a tenfold or hundredfold error. Clinical
reasoning: first identify exactly what the stem is testing—such as drug class, mechanism, indication,
expected effect, adverse reaction, contraindication, monitoring priority, or patient teaching—then select
the option that answers that dimension most directly. Safety connection: the correct response links
pharmacology knowledge to prevention of medication error, recognition of toxicity or deterioration, and
appropriate follow-up. Why the distractors are incorrect: some alternatives may describe a different
property of the drug or class, while others conflict with the requested clinical priority or with safe
medication-use principles.
2. Calculate 1/2 - 1/2. Give the answer in simplest form.
A. 0
B. 3/4
C. 2/3
D. 1/2
Answer: A — 0
Rationale: Convert to compatible fractions or multiply numerators and denominators as required. The
exact result simplifies to 0; reducing the fraction removes common factors and gives the safest form for
later dosage work. Calculation reasoning: keep the units visible through the setup so incompatible units
are converted before arithmetic and the unwanted units cancel. Round only at the final step unless the
problem or institutional policy specifies otherwise, then perform a reasonableness check against the
ordered dose, available concentration, route, and clinical context. Why the distractors are incorrect:
alternative numeric choices commonly result from reversing desired and available quantities, omitting a
conversion, multiplying instead of dividing, using the wrong time unit, or rounding too early.
3. Calculate 1/4 + 1/2. Give the answer in simplest form.
A. 1/2
B. 2/3
C. 3/4
Page 3
, D. Alternative response 4
Answer: C — 3/4
Rationale: Convert to compatible fractions or multiply numerators and denominators as required. The
exact result simplifies to 3/4; reducing the fraction removes common factors and gives the safest form
for later dosage work. Calculation reasoning: keep the units visible through the setup so incompatible
units are converted before arithmetic and the unwanted units cancel. Round only at the final step unless
the problem or institutional policy specifies otherwise, then perform a reasonableness check against the
ordered dose, available concentration, route, and clinical context. Why the distractors are incorrect:
alternative numeric choices commonly result from reversing desired and available quantities, omitting a
conversion, multiplying instead of dividing, using the wrong time unit, or rounding too early.
4. What is 25% of 120?
A. 95
B. 3
C. 35
D. 30
Answer: D — 30
Rationale: Convert 25% to 0.25 and multiply by 120. 0.25 × 120 = 30. Percent means “per 100,” so
dividing the percent by 100 before multiplying prevents a tenfold or hundredfold error. Clinical
reasoning: first identify exactly what the stem is testing—such as drug class, mechanism, indication,
expected effect, adverse reaction, contraindication, monitoring priority, or patient teaching—then select
the option that answers that dimension most directly. Safety connection: the correct response links
pharmacology knowledge to prevention of medication error, recognition of toxicity or deterioration, and
appropriate follow-up. Why the distractors are incorrect: some alternatives may describe a different
property of the drug or class, while others conflict with the requested clinical priority or with safe
medication-use principles.
5. Calculate 1/3 + 1/8. Give the answer in simplest form.
A. 3/4
B. 11/24
C. 2/3
D. 1/2
Answer: B — 11/24
Rationale: Convert to compatible fractions or multiply numerators and denominators as required. The
exact result simplifies to 11/24; reducing the fraction removes common factors and gives the safest form
for later dosage work. Calculation reasoning: keep the units visible through the setup so incompatible
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