CALCULATION OF DRUG
DOSAGES: A WORK TEXT
12TH EDITION
AUTHOR(S)SHEILA J. OGDEN;
LINDA FLUHARTY
TEST BANK
1. Reference: Equivalent Fractions — Tablet Splitting
Clinical Stem: A provider orders 1/2 tablet of an oral analgesic.
The pharmacy sends a scored tablet that can be divided into 4
equal parts. The nurse wants to verify the amount before
administering the dose.
,Options:
A. 1/4 tablet
B. 2/4 tablet
C. 3/4 tablet
D. 4/4 tablet
Correct Answer: B. 2/4 tablet
Rationale — Correct Answer:
One-half is equivalent to 2/4. The nurse should recognize that
the scored tablet can be divided into four equal parts, and
giving two parts delivers the ordered dose. This prevents an
underdose or overdose caused by poor fraction recognition.
Rationale — Incorrect Options:
A. 1/4 tablet: This is only half of the ordered amount and
would underdose the patient.
C. 3/4 tablet: This exceeds the prescribed dose and could
cause medication toxicity.
D. 4/4 tablet: This is a full tablet, not the ordered half-tablet
dose.
Teaching Point: Equivalent fractions must match the ordered
dose exactly.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
, 2. Reference: Simplifying Fractions — Oral Medication Dose
Clinical Stem: A patient is prescribed 3/6 tablet of a sedative at
bedtime. Before administering, the nurse simplifies the fraction
to confirm the dose is correct.
Options:
A. 1/6 tablet
B. 1/2 tablet
C. 2/6 tablet
D. 3/4 tablet
Correct Answer: B. 1/2 tablet
Rationale — Correct Answer:
The fraction 3/6 simplifies to 1/2 because both numerator and
denominator can be divided by 3. Simplifying helps the nurse
verify that the dose matches the prescriber’s intent and
reduces calculation errors.
Rationale — Incorrect Options:
A. 1/6 tablet: This is too small and does not equal 3/6.
C. 2/6 tablet: This is not fully simplified and is less than the
ordered dose.
D. 3/4 tablet: This is larger than 1/2 and would be unsafe.
Teaching Point: Simplify fractions before giving medication.
,Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
3. Reference: Adding Fractions — Total Oral Dose
Clinical Stem: A provider orders 1/4 tablet of one
antihypertensive and 1/2 tablet of another medication to be
given together. The nurse calculates the total number of tablet
parts to administer.
Options:
A. 1/4 tablet
B. 1/2 tablet
C. 3/4 tablet
D. 1 1/4 tablets
Correct Answer: C. 3/4 tablet
Rationale — Correct Answer:
Convert 1/2 to 2/4, then add: 1/4 + 2/4 = 3/4. The nurse must
combine fractions correctly to avoid giving too little or too
much medication.
Rationale — Incorrect Options:
A. 1/4 tablet: This ignores the second ordered dose.
B. 1/2 tablet: This is less than the total prescribed amount.
,D. 1 1/4 tablets: This is too much and reflects an addition
error.
Teaching Point: Convert fractions to a common denominator
before adding.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
4. Reference: Subtracting Fractions — Remaining Dose
Clinical Stem: A patient has already received 1/4 tablet of a
prescribed 3/4 tablet dose. The nurse is preparing the
remainder for the scheduled administration.
Options:
A. 1/4 tablet
B. 1/2 tablet
C. 3/4 tablet
D. 1 tablet
Correct Answer: B. 1/2 tablet
Rationale — Correct Answer:
The remaining dose is 3/4 - 1/4 = 2/4, which simplifies to 1/2.
The nurse must calculate the remainder accurately so the
patient receives the full ordered amount without exceeding it.
,Rationale — Incorrect Options:
A. 1/4 tablet: This would leave the patient short of the
prescribed dose.
C. 3/4 tablet: This would repeat the full dose and risk
overdose.
D. 1 tablet: This exceeds the order and is unsafe.
Teaching Point: Subtract only after converting to a common
denominator.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
5. Reference: Fractional Weight-Based Dose — mg/kg
Clinical Stem: A child weighs 12 kg and is prescribed 1/2 mg/kg
of a medication. The nurse calculates the total dose before
administration.
Options:
A. 3 mg
B. 6 mg
C. 12 mg
D. 24 mg
Correct Answer: B. 6 mg
,Rationale — Correct Answer:
Multiply 12 kg × 1/2 mg/kg = 6 mg. Using the correct fraction
prevents underdosing or overdosing in a pediatric patient,
where small errors can be significant.
Rationale — Incorrect Options:
A. 3 mg: This reflects multiplying by 1/4 instead of 1/2.
C. 12 mg: This ignores the fractional part of the order.
D. 24 mg: This doubles the ordered dose and is unsafe.
Teaching Point: Fractional weight-based orders require exact
multiplication.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
6. Reference: Dividing a Daily Fractional Dose — BID
Schedule
Clinical Stem: A patient is prescribed 1 1/2 tablets per day,
divided into 2 equal doses. The nurse calculates the amount for
each dose.
Options:
A. 1/2 tablet
B. 3/4 tablet
,C. 1 tablet
D. 1 1/2 tablets
Correct Answer: B. 3/4 tablet
Rationale — Correct Answer:
Convert 1 1/2 to 3/2, then divide by 2: 3/2 ÷ 2 = 3/4. Dividing
the daily amount correctly ensures each dose is accurate and
evenly spaced.
Rationale — Incorrect Options:
A. 1/2 tablet: This is too little for each dose.
C. 1 tablet: This would exceed the divided dose.
D. 1 1/2 tablets: This gives the full daily amount at once.
Teaching Point: Convert mixed numbers before dividing a dose.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
7. Reference: Comparing Fractions — Safe Dose Verification
Clinical Stem: Two patients are discussed during handoff. One
is scheduled for 1/8 tablet and the other for 1/4 tablet of the
same medication. The nurse must identify the larger dose.
Options:
A. 1/8 tablet
,B. 1/4 tablet
C. They are equal
D. Neither can be compared
Correct Answer: B. 1/4 tablet
Rationale — Correct Answer:
1/4 is larger than 1/8 because the whole is divided into fewer
parts. Nurses must compare fractions correctly so they do not
mistake a smaller dose for a larger one.
Rationale — Incorrect Options:
A. 1/8 tablet: This is the smaller dose.
C. They are equal: They are not equal because the
denominators differ.
D. Neither can be compared: Fractions can be compared by
size or by using common denominators.
Teaching Point: A smaller denominator usually means a larger
fraction.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
8. Reference: Adding Fractions — Liquid Medication Amount
, Clinical Stem: A provider orders 2/3 mg of a medication now
and an additional 1/6 mg one hour later. The nurse calculates
the total dose the patient will receive.
Options:
A. 1/2 mg
B. 2/3 mg
C. 5/6 mg
D. 1 1/6 mg
Correct Answer: C. 5/6 mg
Rationale — Correct Answer:
Convert 2/3 to 4/6, then add 1/6 to get 5/6 mg. The nurse
must use a common denominator to accurately track the total
medication administered.
Rationale — Incorrect Options:
A. 1/2 mg: This is less than the total ordered dose.
B. 2/3 mg: This ignores the second dose.
D. 1 1/6 mg: This reflects an addition error and gives too much
medication.
Teaching Point: Add fractions by using a common denominator.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
DOSAGES: A WORK TEXT
12TH EDITION
AUTHOR(S)SHEILA J. OGDEN;
LINDA FLUHARTY
TEST BANK
1. Reference: Equivalent Fractions — Tablet Splitting
Clinical Stem: A provider orders 1/2 tablet of an oral analgesic.
The pharmacy sends a scored tablet that can be divided into 4
equal parts. The nurse wants to verify the amount before
administering the dose.
,Options:
A. 1/4 tablet
B. 2/4 tablet
C. 3/4 tablet
D. 4/4 tablet
Correct Answer: B. 2/4 tablet
Rationale — Correct Answer:
One-half is equivalent to 2/4. The nurse should recognize that
the scored tablet can be divided into four equal parts, and
giving two parts delivers the ordered dose. This prevents an
underdose or overdose caused by poor fraction recognition.
Rationale — Incorrect Options:
A. 1/4 tablet: This is only half of the ordered amount and
would underdose the patient.
C. 3/4 tablet: This exceeds the prescribed dose and could
cause medication toxicity.
D. 4/4 tablet: This is a full tablet, not the ordered half-tablet
dose.
Teaching Point: Equivalent fractions must match the ordered
dose exactly.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
, 2. Reference: Simplifying Fractions — Oral Medication Dose
Clinical Stem: A patient is prescribed 3/6 tablet of a sedative at
bedtime. Before administering, the nurse simplifies the fraction
to confirm the dose is correct.
Options:
A. 1/6 tablet
B. 1/2 tablet
C. 2/6 tablet
D. 3/4 tablet
Correct Answer: B. 1/2 tablet
Rationale — Correct Answer:
The fraction 3/6 simplifies to 1/2 because both numerator and
denominator can be divided by 3. Simplifying helps the nurse
verify that the dose matches the prescriber’s intent and
reduces calculation errors.
Rationale — Incorrect Options:
A. 1/6 tablet: This is too small and does not equal 3/6.
C. 2/6 tablet: This is not fully simplified and is less than the
ordered dose.
D. 3/4 tablet: This is larger than 1/2 and would be unsafe.
Teaching Point: Simplify fractions before giving medication.
,Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
3. Reference: Adding Fractions — Total Oral Dose
Clinical Stem: A provider orders 1/4 tablet of one
antihypertensive and 1/2 tablet of another medication to be
given together. The nurse calculates the total number of tablet
parts to administer.
Options:
A. 1/4 tablet
B. 1/2 tablet
C. 3/4 tablet
D. 1 1/4 tablets
Correct Answer: C. 3/4 tablet
Rationale — Correct Answer:
Convert 1/2 to 2/4, then add: 1/4 + 2/4 = 3/4. The nurse must
combine fractions correctly to avoid giving too little or too
much medication.
Rationale — Incorrect Options:
A. 1/4 tablet: This ignores the second ordered dose.
B. 1/2 tablet: This is less than the total prescribed amount.
,D. 1 1/4 tablets: This is too much and reflects an addition
error.
Teaching Point: Convert fractions to a common denominator
before adding.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
4. Reference: Subtracting Fractions — Remaining Dose
Clinical Stem: A patient has already received 1/4 tablet of a
prescribed 3/4 tablet dose. The nurse is preparing the
remainder for the scheduled administration.
Options:
A. 1/4 tablet
B. 1/2 tablet
C. 3/4 tablet
D. 1 tablet
Correct Answer: B. 1/2 tablet
Rationale — Correct Answer:
The remaining dose is 3/4 - 1/4 = 2/4, which simplifies to 1/2.
The nurse must calculate the remainder accurately so the
patient receives the full ordered amount without exceeding it.
,Rationale — Incorrect Options:
A. 1/4 tablet: This would leave the patient short of the
prescribed dose.
C. 3/4 tablet: This would repeat the full dose and risk
overdose.
D. 1 tablet: This exceeds the order and is unsafe.
Teaching Point: Subtract only after converting to a common
denominator.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
5. Reference: Fractional Weight-Based Dose — mg/kg
Clinical Stem: A child weighs 12 kg and is prescribed 1/2 mg/kg
of a medication. The nurse calculates the total dose before
administration.
Options:
A. 3 mg
B. 6 mg
C. 12 mg
D. 24 mg
Correct Answer: B. 6 mg
,Rationale — Correct Answer:
Multiply 12 kg × 1/2 mg/kg = 6 mg. Using the correct fraction
prevents underdosing or overdosing in a pediatric patient,
where small errors can be significant.
Rationale — Incorrect Options:
A. 3 mg: This reflects multiplying by 1/4 instead of 1/2.
C. 12 mg: This ignores the fractional part of the order.
D. 24 mg: This doubles the ordered dose and is unsafe.
Teaching Point: Fractional weight-based orders require exact
multiplication.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
6. Reference: Dividing a Daily Fractional Dose — BID
Schedule
Clinical Stem: A patient is prescribed 1 1/2 tablets per day,
divided into 2 equal doses. The nurse calculates the amount for
each dose.
Options:
A. 1/2 tablet
B. 3/4 tablet
,C. 1 tablet
D. 1 1/2 tablets
Correct Answer: B. 3/4 tablet
Rationale — Correct Answer:
Convert 1 1/2 to 3/2, then divide by 2: 3/2 ÷ 2 = 3/4. Dividing
the daily amount correctly ensures each dose is accurate and
evenly spaced.
Rationale — Incorrect Options:
A. 1/2 tablet: This is too little for each dose.
C. 1 tablet: This would exceed the divided dose.
D. 1 1/2 tablets: This gives the full daily amount at once.
Teaching Point: Convert mixed numbers before dividing a dose.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
7. Reference: Comparing Fractions — Safe Dose Verification
Clinical Stem: Two patients are discussed during handoff. One
is scheduled for 1/8 tablet and the other for 1/4 tablet of the
same medication. The nurse must identify the larger dose.
Options:
A. 1/8 tablet
,B. 1/4 tablet
C. They are equal
D. Neither can be compared
Correct Answer: B. 1/4 tablet
Rationale — Correct Answer:
1/4 is larger than 1/8 because the whole is divided into fewer
parts. Nurses must compare fractions correctly so they do not
mistake a smaller dose for a larger one.
Rationale — Incorrect Options:
A. 1/8 tablet: This is the smaller dose.
C. They are equal: They are not equal because the
denominators differ.
D. Neither can be compared: Fractions can be compared by
size or by using common denominators.
Teaching Point: A smaller denominator usually means a larger
fraction.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
8. Reference: Adding Fractions — Liquid Medication Amount
, Clinical Stem: A provider orders 2/3 mg of a medication now
and an additional 1/6 mg one hour later. The nurse calculates
the total dose the patient will receive.
Options:
A. 1/2 mg
B. 2/3 mg
C. 5/6 mg
D. 1 1/6 mg
Correct Answer: C. 5/6 mg
Rationale — Correct Answer:
Convert 2/3 to 4/6, then add 1/6 to get 5/6 mg. The nurse
must use a common denominator to accurately track the total
medication administered.
Rationale — Incorrect Options:
A. 1/2 mg: This is less than the total ordered dose.
B. 2/3 mg: This ignores the second dose.
D. 1 1/6 mg: This reflects an addition error and gives too much
medication.
Teaching Point: Add fractions by using a common denominator.
Citation: Ogden, S. J., & Fluharty, L. (n.d.). Calculation of Drug
Dosages: A Work Text (Chapter 1: Fractions PRETEST).
