Calculating Drug Dosages: A Patient-Safe Approach
to Nursing and Math Test Bank Questions 1–100:
(2nd Edition) | Advanced/Hard Difficulty | 100%
Pass Guaranteed | Graded A+
1. A nurse is preparing to administer 500 mg of a medication. The available medication is in a
liquid concentration of 250 mg/5 mL. How many mL will the nurse administer?
A. 5 mL
B. 10 mL
C. 15 mL
D. 20 mL
Correct Answer: B
Explanation: Using the formula Desired/Have x Quantity: 500 mg / 250 mg x 5 mL = 2 x 5 mL =
10 mL. Option A (5 mL) is the volume for 250 mg. Option C (15 mL) is incorrect. Option D (20 mL)
is incorrect.
2. A patient is prescribed 0.5 g of a medication. The medication is available in 250 mg tablets.
How many tablets should the nurse administer?
,A. 1 tablet
B. 2 tablets
C. 3 tablets
D. 4 tablets
Correct Answer: B
Explanation: First convert 0.5 g to mg: 0.5 g x 1000 = 500 mg. Then 500 mg / 250 mg per tablet
= 2 tablets. Option A (1 tablet) is the dose for 250 mg. Option C (3 tablets) is incorrect. Option D
(4 tablets) is incorrect.
3. A nurse is infusing 1000 mL of normal saline over 8 hours. The drop factor of the IV tubing is
15 gtt/mL. What is the flow rate in drops per minute (gtt/min)? (Round to the nearest whole
number.)
A. 21 gtt/min
B. 31 gtt/min
C. 41 gtt/min
D. 51 gtt/min
,Correct Answer: B
Explanation: Total volume (1000 mL) / Total time (8 hours x 60 min = 480 min) = 2.08 mL/min.
Then 2.08 mL/min x 15 gtt/mL = 31.25 ≈ 31 gtt/min. Option A (21 gtt/min) is too low. Option C
(41 gtt/min) is too high. Option D (51 gtt/min) is significantly too high.
4. A patient is prescribed 25 mg of a medication. The pharmacy sends a vial labeled 100 mg/2
mL. How many mL will the nurse administer?
A. 0.25 mL
B. 0.5 mL
C. 1 mL
D. 2 mL
Correct Answer: B
Explanation: Desired/Have x Quantity: 25 mg / 100 mg x 2 mL = 0.25 x 2 = 0.5 mL. Option A
(0.25 mL) is incorrect. Option C (1 mL) is the volume for 50 mg. Option D (2 mL) is the volume for
100 mg.
, 5. A nurse is preparing to administer 3000 mL of D5W over 24 hours. The drop factor is 20
gtt/mL. Calculate the flow rate in gtt/min. (Round to the nearest whole number.)
A. 32 gtt/min
B. 42 gtt/min
C. 52 gtt/min
D. 62 gtt/min
Correct Answer: B
Explanation: Total volume (3000 mL) / Total time (24 hours x 60 = 1440 min) = 2.08 mL/min.
2.08 mL/min x 20 gtt/mL = 41.6 ≈ 42 gtt/min. Option A (32 gtt/min) is too low. Option C (52
gtt/min) is too high. Option D (62 gtt/min) is incorrect.
6. A patient has an order for 1500 mL of lactated Ringer's to infuse over 10 hours. The IV tubing
has a drop factor of 10 gtt/mL. Calculate the flow rate in gtt/min. (Round to the nearest whole
number.)
A. 20 gtt/min
B. 25 gtt/min
to Nursing and Math Test Bank Questions 1–100:
(2nd Edition) | Advanced/Hard Difficulty | 100%
Pass Guaranteed | Graded A+
1. A nurse is preparing to administer 500 mg of a medication. The available medication is in a
liquid concentration of 250 mg/5 mL. How many mL will the nurse administer?
A. 5 mL
B. 10 mL
C. 15 mL
D. 20 mL
Correct Answer: B
Explanation: Using the formula Desired/Have x Quantity: 500 mg / 250 mg x 5 mL = 2 x 5 mL =
10 mL. Option A (5 mL) is the volume for 250 mg. Option C (15 mL) is incorrect. Option D (20 mL)
is incorrect.
2. A patient is prescribed 0.5 g of a medication. The medication is available in 250 mg tablets.
How many tablets should the nurse administer?
,A. 1 tablet
B. 2 tablets
C. 3 tablets
D. 4 tablets
Correct Answer: B
Explanation: First convert 0.5 g to mg: 0.5 g x 1000 = 500 mg. Then 500 mg / 250 mg per tablet
= 2 tablets. Option A (1 tablet) is the dose for 250 mg. Option C (3 tablets) is incorrect. Option D
(4 tablets) is incorrect.
3. A nurse is infusing 1000 mL of normal saline over 8 hours. The drop factor of the IV tubing is
15 gtt/mL. What is the flow rate in drops per minute (gtt/min)? (Round to the nearest whole
number.)
A. 21 gtt/min
B. 31 gtt/min
C. 41 gtt/min
D. 51 gtt/min
,Correct Answer: B
Explanation: Total volume (1000 mL) / Total time (8 hours x 60 min = 480 min) = 2.08 mL/min.
Then 2.08 mL/min x 15 gtt/mL = 31.25 ≈ 31 gtt/min. Option A (21 gtt/min) is too low. Option C
(41 gtt/min) is too high. Option D (51 gtt/min) is significantly too high.
4. A patient is prescribed 25 mg of a medication. The pharmacy sends a vial labeled 100 mg/2
mL. How many mL will the nurse administer?
A. 0.25 mL
B. 0.5 mL
C. 1 mL
D. 2 mL
Correct Answer: B
Explanation: Desired/Have x Quantity: 25 mg / 100 mg x 2 mL = 0.25 x 2 = 0.5 mL. Option A
(0.25 mL) is incorrect. Option C (1 mL) is the volume for 50 mg. Option D (2 mL) is the volume for
100 mg.
, 5. A nurse is preparing to administer 3000 mL of D5W over 24 hours. The drop factor is 20
gtt/mL. Calculate the flow rate in gtt/min. (Round to the nearest whole number.)
A. 32 gtt/min
B. 42 gtt/min
C. 52 gtt/min
D. 62 gtt/min
Correct Answer: B
Explanation: Total volume (3000 mL) / Total time (24 hours x 60 = 1440 min) = 2.08 mL/min.
2.08 mL/min x 20 gtt/mL = 41.6 ≈ 42 gtt/min. Option A (32 gtt/min) is too low. Option C (52
gtt/min) is too high. Option D (62 gtt/min) is incorrect.
6. A patient has an order for 1500 mL of lactated Ringer's to infuse over 10 hours. The IV tubing
has a drop factor of 10 gtt/mL. Calculate the flow rate in gtt/min. (Round to the nearest whole
number.)
A. 20 gtt/min
B. 25 gtt/min
