Relias RN Advanced Math Ability V3 | Q&A
with Rationale
1. A physician orders Heparin at 1,400 units/hr. The concentration is 25,000 units in 500 mL of
0.45% Normal Saline. At what rate should the IV pump be set in mL/hr?
A. 24 mL/hr
B. 32 mL/hr
C. 28 mL/hr
D. 36 mL/hr
Correct Answer: C
Rationale: To solve this, divide the desired hourly dose of 1,400 units by the total units in
the bag, 25,000 units. Multiply the result by the volume of 500 mL. The calculation (1,400 /
25,000) * 500 results in exactly 28 mL/hr. This ensures the patient receives the specific
anticoagulant dose ordered per clinical protocol.
2. An order is written for Dopamine 5 mcg/kg/min for a patient weighing 80 kg. The available
concentration is 400 mg in 250 mL D5W. What is the infusion rate in mL/hr?
A. 15 mL/hr
B. 20 mL/hr
C. 25 mL/hr
,D. 30 mL/hr
Correct Answer: A
Rationale: First, calculate the mcg/min by multiplying 5 mcg * 80 kg, which equals 400
mcg/min. Convert the concentration to mcg/mL by dividing 400,000 mcg (400 mg) by 250
mL, resulting in 1,600 mcg/mL. Finally, divide 400 mcg/min by 1,600 mcg/mL and
multiply by 60 minutes to reach 15 mL/hr.
3. A patient is to receive 1 gram of Vancomycin in 250 mL of Normal Saline over 90 minutes.
What is the rate in mL/hr?
A. 167 mL/hr
B. 150 mL/hr
C. 125 mL/hr
D. 180 mL/hr
Correct Answer: A
Rationale: To find the hourly rate, divide the total volume of 250 mL by the total time of 90
minutes. Multiply the resulting value by 60 minutes to determine the rate for a full hour.
The calculation * 60 equals 166.67, which rounds to 167 mL/hr as per standard
nursing practice.
4. The healthcare provider orders 0.375 mg of Digoxin IV push. The vial is labeled 0.25
mg/mL. How many mL should the nurse administer?
A. 1.2 mL
, B. 2.0 mL
C. 0.75 mL
D. 1.5 mL
Correct Answer: D
Rationale: The formula used is Desired dose divided by Have dose multiplied by Volume.
In this case, 0.375 mg divided by 0.25 mg equals 1.5. Multiplying by 1 mL confirms that the
nurse must draw up and administer 1.5 mL.
5. A pediatric patient weighs 44 lbs. The ordered dose is 15 mg/kg. How many mg will the
patient receive?
A. 660 mg
B. 450 mg
C. 600 mg
D. 300 mg
Correct Answer: D
Rationale: First, convert the weight from pounds to kilograms by dividing 44 lbs by 2.2,
which equals 20 kg. Then, multiply the weight of 20 kg by the ordered dose of 15 mg/kg.
This results in a total dosage of 300 mg to be administered safely to the child.
with Rationale
1. A physician orders Heparin at 1,400 units/hr. The concentration is 25,000 units in 500 mL of
0.45% Normal Saline. At what rate should the IV pump be set in mL/hr?
A. 24 mL/hr
B. 32 mL/hr
C. 28 mL/hr
D. 36 mL/hr
Correct Answer: C
Rationale: To solve this, divide the desired hourly dose of 1,400 units by the total units in
the bag, 25,000 units. Multiply the result by the volume of 500 mL. The calculation (1,400 /
25,000) * 500 results in exactly 28 mL/hr. This ensures the patient receives the specific
anticoagulant dose ordered per clinical protocol.
2. An order is written for Dopamine 5 mcg/kg/min for a patient weighing 80 kg. The available
concentration is 400 mg in 250 mL D5W. What is the infusion rate in mL/hr?
A. 15 mL/hr
B. 20 mL/hr
C. 25 mL/hr
,D. 30 mL/hr
Correct Answer: A
Rationale: First, calculate the mcg/min by multiplying 5 mcg * 80 kg, which equals 400
mcg/min. Convert the concentration to mcg/mL by dividing 400,000 mcg (400 mg) by 250
mL, resulting in 1,600 mcg/mL. Finally, divide 400 mcg/min by 1,600 mcg/mL and
multiply by 60 minutes to reach 15 mL/hr.
3. A patient is to receive 1 gram of Vancomycin in 250 mL of Normal Saline over 90 minutes.
What is the rate in mL/hr?
A. 167 mL/hr
B. 150 mL/hr
C. 125 mL/hr
D. 180 mL/hr
Correct Answer: A
Rationale: To find the hourly rate, divide the total volume of 250 mL by the total time of 90
minutes. Multiply the resulting value by 60 minutes to determine the rate for a full hour.
The calculation * 60 equals 166.67, which rounds to 167 mL/hr as per standard
nursing practice.
4. The healthcare provider orders 0.375 mg of Digoxin IV push. The vial is labeled 0.25
mg/mL. How many mL should the nurse administer?
A. 1.2 mL
, B. 2.0 mL
C. 0.75 mL
D. 1.5 mL
Correct Answer: D
Rationale: The formula used is Desired dose divided by Have dose multiplied by Volume.
In this case, 0.375 mg divided by 0.25 mg equals 1.5. Multiplying by 1 mL confirms that the
nurse must draw up and administer 1.5 mL.
5. A pediatric patient weighs 44 lbs. The ordered dose is 15 mg/kg. How many mg will the
patient receive?
A. 660 mg
B. 450 mg
C. 600 mg
D. 300 mg
Correct Answer: D
Rationale: First, convert the weight from pounds to kilograms by dividing 44 lbs by 2.2,
which equals 20 kg. Then, multiply the weight of 20 kg by the ordered dose of 15 mg/kg.
This results in a total dosage of 300 mg to be administered safely to the child.