ATI Basic Dosage Calculations: Complete Nursing Medication Math Mastery Guide for Safe and Accurate Drug Administration, Dimensional Analysis, Formula & Ratio-Proportion Methods, Oral, Injectable & IV Dosage Calculations, IV Flow Rate & Infusion Rat

ATI Basic Dosage Calculations: Complete Nursing Medication Math Mastery
Guide for Safe and Accurate Drug Administration, Dimensional Analysis,
Formula & Ratio-Proportion Methods, Oral, Injectable & IV Dosage Calculations,
IV Flow Rate & Infusion Rate Calculations, Pediatric & Adult Medication Dosage
Problems, Weight-Based Calculations, Unit Conversions, Practice Questions with
Detailed Rationales, ATI RN Fundamentals Review, NCLEX-RN Exam Preparation
& Nursing School Success Study Guide
Question 1
A nurse is preparing to administer a medication that is available in 0.5 g tablets.
The provider orders 500 mg. How many tablets should the nurse administer?
A. 0.5 tablet
B. 1 tablet
C. 2 tablets
D. 1.5 tablets
Correct Answer: B
Rationale: Convert 0.5 g to mg: 0.5 g × 1000 = 500 mg. The order is for 500 mg
and each tablet contains 500 mg. Therefore, 500 mg ÷ 500 mg/tablet = 1 tablet.


Question 2
A nurse needs to convert a patient's weight from 154 lb to kg. What is the weight
in kilograms?
A. 60 kg
B. 65 kg
C. 70 kg
D. 75 kg
Correct Answer: C
Rationale: Use the conversion factor 1 kg = 2.2 lb. 154 lb ÷ 2.2 = 70 kg. Always
convert pounds to kilograms for weight-based dosing calculations.

,Question 3
A medication is available in a concentration of 250 mg/5 mL. How many
milligrams are in 15 mL?
A. 500 mg
B. 650 mg
C. 750 mg
D. 850 mg
Correct Answer: C
Rationale: Set up a proportion: 250 mg/5 mL = x mg/15 mL. Cross-multiply: 5x =
250 × 15 = 3750. x = 3750 ÷ 5 = 750 mg.


Question 4
A nurse is administering 0.05 g of a medication. How many milligrams is this
equivalent to?
A. 5 mg
B. 50 mg
C. 500 mg
D. 0.5 mg
Correct Answer: B
Rationale: Convert grams to milligrams: 0.05 g × 1000 = 50 mg. Remember: 1 g =
1000 mg.


Question 5
A patient weighs 220 lb. What is this weight in kilograms?
A. 90 kg
B. 95 kg
C. 100 kg
D. 110 kg
Correct Answer: C

,Rationale: 220 lb ÷ 2.2 = 100 kg. Knowing this conversion is essential for weight-
based calculations.


Question 6
How many milliliters are in 4 tablespoons?
A. 30 mL
B. 45 mL
C. 60 mL
D. 90 mL
Correct Answer: C
Rationale: 1 tablespoon = 15 mL. 4 tablespoons × 15 mL = 60 mL.


Question 7
A provider orders 1.5 L of fluid over 24 hours. How many milliliters is this?
A. 150 mL
B. 1500 mL
C. 15,000 mL
D. 150,000 mL
Correct Answer: B
Rationale: 1 L = 1000 mL. 1.5 L × 1000 = 1500 mL.


Question 8
A nurse has a medication vial labeled 1 mg/mL. The order is for 500 mcg. How
many mL should the nurse administer?
A. 0.5 mL
B. 1 mL
C. 1.5 mL
D. 2 mL
Correct Answer: A

, Rationale: Convert 500 mcg to mg: 500 mcg ÷ 1000 = 0.5 mg. The concentration is
1 mg/mL, so 0.5 mg ÷ 1 mg/mL = 0.5 mL.


Question 9
How many teaspoons are in 30 mL?
A. 2 tsp
B. 4 tsp
C. 6 tsp
D. 8 tsp
Correct Answer: C
Rationale: 1 teaspoon = 5 mL. 30 mL ÷ 5 mL/tsp = 6 tsp.


Question 10
A medication is available as 0.25 mg per tablet. The order is for 250 mcg. How
many tablets should the nurse administer?
A. 0.5 tablet
B. 1 tablet
C. 1.5 tablets
D. 2 tablets
Correct Answer: B
Rationale: Convert 250 mcg to mg: 250 ÷ 1000 = 0.25 mg. Each tablet contains
0.25 mg, so 0.25 mg ÷ 0.25 mg/tablet = 1 tablet.


Questions 11–20: Oral Solid Medications (Tablets/Capsules)
Question 11
A provider prescribes 500 mg of a medication. The available tablets are 250 mg
each. How many tablets should the nurse administer?
A. 1 tablet
B. 1.5 tablets