Solving Problems Using Dimensional

DOSAGE CALCULATIONS MADE
EASY
SOLVING PROBLEMS USING
DIMENSIONAL ANALYSIS
8TH EDITION
• AUTHOR(S)GLORIA PEARL
CRAIG




TEST BANK

,Question 1 (Easy) – Dimensional Analysis Fundamentals
A healthcare provider prescribes acetaminophen 650 mg PO for
an adult with a fever. The medication label reads 325 mg per
tablet.
How many tablets should the nurse administer?
A. 1 tablet
B. 1.5 tablets
C. 2 tablets
D. 2.5 tablets
Correct Answer: C. 2 tablets
Rationale:
Step 1: Identify the prescribed dose and available strength.
• Ordered = 650 mg
• Available = 325 mg/tablet
Step 2: Set up dimensional analysis.
[
650\ \text{mg} \times \frac{1\ \text{tablet}}{325\ \text{mg}} =
2\ \text{tablets}
]

,The milligrams cancel, leaving tablets.
Step 3: Verify the answer.
325 mg × 2 tablets = 650 mg ✔
Medication Safety Note:
Always verify that scored tablets may be split if a partial tablet
is required. Since a whole-number dose is obtained, no tablet
splitting is needed.


Question 2 (Easy) – Oral Liquid Calculation
A patient is prescribed amoxicillin 500 mg PO. The pharmacy
dispenses 250 mg per 5 mL.
How many milliliters should the nurse administer?
A. 5 mL
B. 8 mL
C. 10 mL
D. 15 mL
Correct Answer: C. 10 mL
Rationale:
Step 1:
Ordered = 500 mg

, Available = 250 mg/5 mL
Step 2: Dimensional analysis
[
500\ \text{mg} \times \frac{5\ \text{mL}}{250\ \text{mg}}=10\
\text{mL}
]
Step 3: Check
250 mg is contained in 5 mL.
Double the dose requires 10 mL.
Medication Safety Note:
Measure liquid medications using an oral syringe or medication
cup marked in milliliters rather than household spoons.


Question 3 (Easy) – Metric Conversion
A medication order requires 0.75 g of an antibiotic.
How many milligrams is this?
A. 75 mg
B. 750 mg
C. 7,500 mg
D. 0.75 mg