HENKE'S MED-MATH
DOSAGE CALCULATION, PREPARATION
& ADMINISTRATION
10TH EDITION
• AUTHOR(S)SUSAN BUCHHOLZ
TEST BANK
1) Reference
Ch. 1 — Multiplying Whole Numbers
Question stem: A provider orders 750 mg of oral
acetaminophen for an adult patient. The medication on the
floor is stocked as 250-mg tablets. How many tablets should the
nurse administer? Show safe preparation and state the dose in
tablets.
A. 2 tablets
B. 2.5 tablets
C. 3 tablets
D. 4 tablets
,Correct answer: C. 3 tablets
Rationale — Correct (C):
750 mg ÷ 250 mg per tablet = 3 tablets. The units cancel (mg ÷
mg → tablets). Multiplication/division of whole numbers yields
an exact whole number, so no splitting is needed. Administering
3 tablets delivers the ordered 750 mg.
Rationale — Incorrect:
A. 2 tablets — Under-doses (2 × 250 = 500 mg); result of
subtracting instead of dividing.
B. 2.5 tablets — Suggests using 625 mg (2.5 × 250) —
underdose; likely from incorrect division (750 ÷ 300 or decimal
misplacement).
D. 4 tablets — Gives 1000 mg (4 × 250) — overdose; likely from
misreading order as 1000 mg.
Teaching point: Always divide ordered dose by strength per
unit; check units cancel.
Citation: Buchholz, S. (2024). Henke’s Med-Math: Dosage
Calculation, Preparation & Administration (10th ed.). Ch. 1.
2) Reference
Ch. 1 — Decimals & Unit Conversion
Question stem: The provider orders 0.5 g of a drug. Available
tablets are 250 mg each. How many tablets are required? Show
unit conversion and calculation.
A. 1 tablet
,B. 2 tablets
C. 3 tablets
D. 4 tablets
Correct answer: B. 2 tablets
Rationale — Correct (B):
Convert grams to milligrams: 0.5 g × 1000 mg/g = 500 mg. Then
500 mg ÷ 250 mg/tablet = 2 tablets. Demonstrates decimal →
whole-number conversion followed by division.
Rationale — Incorrect:
A. 1 tablet — Would be 250 mg; error from not converting
grams to mg.
C. 3 tablets — 3 × 250 = 750 mg; suggests converting 0.5 g to
750 mg (wrong multiplier).
D. 4 tablets — 1000 mg; likely misreading 0.5 g as 1 g.
Teaching point: Convert all doses into the same units before
dividing.
Citation: Buchholz, S. (2024). Henke’s Med-Math: Dosage
Calculation, Preparation & Administration (10th ed.). Ch. 1.
3) Reference
Ch. 1 — Dividing Whole Numbers (Rate Calculations)
Question stem: An IV bag contains 1000 mL of normal saline.
The provider orders the infusion to run over 8 hours. Using
whole-number division, calculate the infusion rate in mL/hr.
, A. 100 mL/hr
B. 125 mL/hr
C. 150 mL/hr
D. 200 mL/hr
Correct answer: B. 125 mL/hr
Rationale — Correct (B):
1000 mL ÷ 8 hr = 125 mL/hr. Units divide to mL/hr; basic whole-
number division yields the hourly rate for pump programming.
Rationale — Incorrect:
A. 100 mL/hr — Underestimates; likely used 10 hours or
dropped a digit (1000 ÷ 10).
C. 150 mL/hr — Common rounding from 1000 ÷ 6.67 hr;
incorrect divisor.
D. 200 mL/hr — Would be 1000 ÷ 5 hr; wrong time used.
Teaching point: Divide total volume by total hours; keep units
consistent (mL/hr).
Citation: Buchholz, S. (2024). Henke’s Med-Math: Dosage
Calculation, Preparation & Administration (10th ed.). Ch. 1.
4) Reference
Ch. 1 — Percents (Concentration to mg/mL)
Question stem: A topical solution is labeled 2% drug X. Using
the percent→mg/mL relationship, what is the concentration in
mg/mL? (Recall: 1% = 10 mg/mL.)
DOSAGE CALCULATION, PREPARATION
& ADMINISTRATION
10TH EDITION
• AUTHOR(S)SUSAN BUCHHOLZ
TEST BANK
1) Reference
Ch. 1 — Multiplying Whole Numbers
Question stem: A provider orders 750 mg of oral
acetaminophen for an adult patient. The medication on the
floor is stocked as 250-mg tablets. How many tablets should the
nurse administer? Show safe preparation and state the dose in
tablets.
A. 2 tablets
B. 2.5 tablets
C. 3 tablets
D. 4 tablets
,Correct answer: C. 3 tablets
Rationale — Correct (C):
750 mg ÷ 250 mg per tablet = 3 tablets. The units cancel (mg ÷
mg → tablets). Multiplication/division of whole numbers yields
an exact whole number, so no splitting is needed. Administering
3 tablets delivers the ordered 750 mg.
Rationale — Incorrect:
A. 2 tablets — Under-doses (2 × 250 = 500 mg); result of
subtracting instead of dividing.
B. 2.5 tablets — Suggests using 625 mg (2.5 × 250) —
underdose; likely from incorrect division (750 ÷ 300 or decimal
misplacement).
D. 4 tablets — Gives 1000 mg (4 × 250) — overdose; likely from
misreading order as 1000 mg.
Teaching point: Always divide ordered dose by strength per
unit; check units cancel.
Citation: Buchholz, S. (2024). Henke’s Med-Math: Dosage
Calculation, Preparation & Administration (10th ed.). Ch. 1.
2) Reference
Ch. 1 — Decimals & Unit Conversion
Question stem: The provider orders 0.5 g of a drug. Available
tablets are 250 mg each. How many tablets are required? Show
unit conversion and calculation.
A. 1 tablet
,B. 2 tablets
C. 3 tablets
D. 4 tablets
Correct answer: B. 2 tablets
Rationale — Correct (B):
Convert grams to milligrams: 0.5 g × 1000 mg/g = 500 mg. Then
500 mg ÷ 250 mg/tablet = 2 tablets. Demonstrates decimal →
whole-number conversion followed by division.
Rationale — Incorrect:
A. 1 tablet — Would be 250 mg; error from not converting
grams to mg.
C. 3 tablets — 3 × 250 = 750 mg; suggests converting 0.5 g to
750 mg (wrong multiplier).
D. 4 tablets — 1000 mg; likely misreading 0.5 g as 1 g.
Teaching point: Convert all doses into the same units before
dividing.
Citation: Buchholz, S. (2024). Henke’s Med-Math: Dosage
Calculation, Preparation & Administration (10th ed.). Ch. 1.
3) Reference
Ch. 1 — Dividing Whole Numbers (Rate Calculations)
Question stem: An IV bag contains 1000 mL of normal saline.
The provider orders the infusion to run over 8 hours. Using
whole-number division, calculate the infusion rate in mL/hr.
, A. 100 mL/hr
B. 125 mL/hr
C. 150 mL/hr
D. 200 mL/hr
Correct answer: B. 125 mL/hr
Rationale — Correct (B):
1000 mL ÷ 8 hr = 125 mL/hr. Units divide to mL/hr; basic whole-
number division yields the hourly rate for pump programming.
Rationale — Incorrect:
A. 100 mL/hr — Underestimates; likely used 10 hours or
dropped a digit (1000 ÷ 10).
C. 150 mL/hr — Common rounding from 1000 ÷ 6.67 hr;
incorrect divisor.
D. 200 mL/hr — Would be 1000 ÷ 5 hr; wrong time used.
Teaching point: Divide total volume by total hours; keep units
consistent (mL/hr).
Citation: Buchholz, S. (2024). Henke’s Med-Math: Dosage
Calculation, Preparation & Administration (10th ed.). Ch. 1.
4) Reference
Ch. 1 — Percents (Concentration to mg/mL)
Question stem: A topical solution is labeled 2% drug X. Using
the percent→mg/mL relationship, what is the concentration in
mg/mL? (Recall: 1% = 10 mg/mL.)
