A 60 gtt/mL administration set is most often used for:

Rapid large-volume fluid boluses

A dopamine infusion ordered in mcg/kg/min requires the paramedic to know:

Weight, bag concentration, and drip set

Only the blood pressure and heart rate

Only the patient's weight in kilograms

Only the bag volume and the drip set

The most common source of dosing error in pediatric patients is:

Weight estimation and decimal errors

Choosing the wrong drug for the condition

Incomplete documentation of the dose

Choosing the wrong route for a child

Medical Math Practice Questions

139 multiple-choice questions on Medical math for paramedic and EMT students, from Chapter 14 (Medication Administration). Read each question, pick your answer, then tap Show answer to check it and read the explanation.

Drill this section: 5 in a row Take the Chapter 14 test

139 practice questions

1 gram equals:
1. A. 100 milligrams
2. B. 10 milligrams
3. C. 1,000 milligrams
4. D. 10,000 milligrams
Show answer
Answer: C. 1,000 milligrams
Each metric step is a factor of 1,000.
1 milligram equals:
1. A. 1,000 micrograms
2. B. 100 micrograms
3. C. 1,000,000 micrograms
4. D. 10 micrograms
Show answer
Answer: A. 1,000 micrograms
Fentanyl is dosed in micrograms, morphine in milligrams.
1 liter equals:
1. A. 1,000 milliliters
2. B. 10,000 milliliters
3. C. 100 milliliters
4. D. 10 milliliters
Show answer
Answer: A. 1,000 milliliters
A liter bag of saline contains 1,000 mL.
1 kilogram equals approximately:
1. A. 1.2 pounds
2. B. 10 pounds
3. C. 5 pounds
4. D. 2.2 pounds
Show answer
Answer: D. 2.2 pounds
Divide pounds by 2.2 to estimate kilograms.
Your hyperkalemia protocol calls for 1 g of calcium chloride, but only 10% calcium gluconate is stocked. About how many grams of calcium gluconate supply the same calcium?
1. A. 1 g
2. B. 0.3 g
3. C. 3 g
4. D. 10 g
Show answer
Answer: C. 3 g
Calcium chloride contains about three times as much elemental calcium per gram as calcium gluconate (about 13.6 vs 4.65 mEq per gram), so about 3 g of calcium gluconate (30 mL of the 10% solution) matches 1 g of the chloride. 1 g would underdose by about two-thirds, 0.3 g reverses the ratio, and 10 g is more than three times too much.
A vial labeled 50 mg in 5 mL has a concentration of:
1. A. 5 mg/mL
2. B. 50 mg/mL
3. C. 25 mg/mL
4. D. 10 mg/mL
Show answer
Answer: D. 10 mg/mL
Divide the total mass by the total volume.
To give 4 mg from a vial containing 10 mg in 10 mL, you administer:
1. A. 8 mL
2. B. 4 mL
3. C. 2 mL
4. D. 0.4 mL
Show answer
Answer: B. 4 mL
The concentration is 1 mg/mL, so 4 mg is 4 mL.
To give 0.3 mg of epinephrine from a 1 mg/mL vial, you administer:
1. A. 0.3 mL
2. B. 0.03 mL
3. C. 0.1 mL
4. D. 3 mL
Show answer
Answer: A. 0.3 mL
The 1 mg/mL concentration is the older 1:1,000 labeling.
1 mg of epinephrine is added to a 1,000-mL bag of saline for an infusion. At 2 mcg/min, what pump rate is needed?
1. A. 120 mL/hr
2. B. 2 mL/hr
3. C. 12 mL/hr
4. D. 1,200 mL/hr
Show answer
Answer: A. 120 mL/hr
1 mg = 1,000 mcg in 1,000 mL = 1 mcg/mL. At 2 mcg/min you need 2 mL/min, and 2 x 60 = 120 mL/hr. 2 mL/hr forgets to convert minutes to hours, and 12 mL/hr and 1,200 mL/hr are tenfold decimal errors.
The desired dose divided by the concentration on hand gives you:
1. A. The drip rate in gtt/min
2. B. The volume to administer
3. C. The infusion rate in mL/hr
4. D. The patient's weight
Show answer
Answer: B. The volume to administer
Desired over have, times the volume.
A drug is ordered at 0.1 mg/kg for a 70 kg patient. The dose is:
1. A. 0.07 mg
2. B. 7 mg
3. C. 0.7 mg
4. D. 70 mg
Show answer
Answer: B. 7 mg
Multiply the weight by the per-kilogram dose.
A 500 mL bag is to infuse over 4 hours using a 10 gtt/mL set. The rate is approximately:
1. A. 2 gtt/min
2. B. 1,250 gtt/min
3. C. 125 gtt/min
4. D. 21 gtt/min
Show answer
Answer: D. 21 gtt/min
500 mL divided by 240 minutes is about 2.1 mL/min, times 10 gtt/mL. Forgetting the drop factor gives 2; using hours instead of minutes gives 1,250.
A 60 gtt/mL administration set is most often used for:
1. A. Trauma resuscitation in shock
2. B. Rapid large-volume fluid boluses
3. C. Blood product administration
4. D. Precise, low-volume infusions
Show answer
Answer: D. Precise, low-volume infusions
Microdrip sets are used for precise low-volume infusions and pediatric patients. It is often called a microdrip set.
To infuse 1,000 mL over 8 hours with a 15 gtt/mL set, the rate is approximately:
1. A. 2 gtt/min
2. B. 125 gtt/min
3. C. 31 gtt/min
4. D. 1,875 gtt/min
Show answer
Answer: C. 31 gtt/min
125 mL/hr is about 2.1 mL/min, times 15 gtt/mL.
A dopamine infusion ordered in mcg/kg/min requires the paramedic to know:
1. A. Only the blood pressure and heart rate
2. B. Weight, bag concentration, and drip set
3. C. Only the patient's weight in kilograms
4. D. Only the bag volume and the drip set
Show answer
Answer: B. Weight, bag concentration, and drip set
You need the patient's weight, the bag concentration, and the drop set or pump settings. Double-check infusion calculations with a partner.
The most common source of dosing error in pediatric patients is:
1. A. Choosing the wrong drug for the condition
2. B. Incomplete documentation of the dose
3. C. Choosing the wrong route for a child
4. D. Weight estimation and decimal errors
Show answer
Answer: D. Weight estimation and decimal errors
Length-based tapes and pre-calculated charts reduce both.
Convert 2.5 grams to milligrams:
1. A. 25,000 mg
2. B. 25 mg
3. C. 2,500 mg
4. D. 250 mg
Show answer
Answer: C. 2,500 mg
1 g = 1,000 mg; 2.5 × 1,000 = 2,500 mg.
Convert 500 micrograms to milligrams:
1. A. 50 mg
2. B. 0.05 mg
3. C. 5 mg
4. D. 0.5 mg
Show answer
Answer: D. 0.5 mg
1 mg = 1,000 mcg; 500 ÷ 1,000 = 0.5 mg.
Convert 0.3 mg to micrograms:
1. A. 3,000 mcg
2. B. 3 mcg
3. C. 300 mcg
4. D. 30 mcg
Show answer
Answer: C. 300 mcg
0.3 × 1,000 = 300 mcg.
A 132-lb woman needs ketamine 0.3 mg/kg IV for pain. What dose should she receive?
1. A. 39.6 mg
2. B. 18 mg
3. C. 180 mg
4. D. 60 mg
Show answer
Answer: B. 18 mg
132 lb / 2.2 = 60 kg, and 60 x 0.3 mg/kg = 18 mg. 39.6 mg comes from multiplying by pounds, 180 mg is a tenfold decimal error, and 60 mg mistakes the weight for the dose.
A child weighs 44 lb. Weight in kg is:
1. A. 20 kg
2. B. 15 kg
3. C. 25 kg
4. D. 22 kg
Show answer
Answer: A. 20 kg
44 ÷ 2.2 = 20 kg.
Convert 1.5 liters to milliliters:
1. A. 150 mL
2. B. 15,000 mL
3. C. 15 mL
4. D. 1,500 mL
Show answer
Answer: D. 1,500 mL
1 L = 1,000 mL.
A vial contains 100 mg in 10 mL. The concentration is:
1. A. 0.1 mg/mL
2. B. 100 mg/mL
3. C. 1 mg/mL
4. D. 10 mg/mL
Show answer
Answer: D. 10 mg/mL
100 ÷ 10 = 10 mg/mL.
Order: 5 mg. On hand: 10 mg/mL. Volume to administer:
1. A. 2 mL
2. B. 0.25 mL
3. C. 1 mL
4. D. 0.5 mL
Show answer
Answer: D. 0.5 mL
Volume = desired ÷ concentration = 5 ÷ 10 = 0.5 mL.
Order: 0.5 mg epinephrine IM. On hand: 1 mg/mL. Volume:
1. A. 0.1 mL
2. B. 0.3 mL
3. C. 1 mL
4. D. 0.5 mL
Show answer
Answer: D. 0.5 mL
0.5 ÷ 1 = 0.5 mL.
Order: 4 mg ondansetron. On hand: 2 mg/mL. Volume:
1. A. 8 mL
2. B. 1 mL
3. C. 4 mL
4. D. 2 mL
Show answer
Answer: D. 2 mL
4 ÷ 2 = 2 mL.
Order: 150 mg amiodarone. On hand: 50 mg/mL. Volume:
1. A. 3 mL
2. B. 7.5 mL
3. C. 1.5 mL
4. D. 5 mL
Show answer
Answer: A. 3 mL
150 ÷ 50 = 3 mL.
A 1:1,000 epinephrine solution contains:
1. A. 1 mg/mL
2. B. 0.01 mg/mL
3. C. 0.1 mg/mL
4. D. 10 mg/mL
Show answer
Answer: A. 1 mg/mL
1:1,000 = 1 g in 1,000 mL = 1 mg/mL.
A 1:10,000 epinephrine solution contains:
1. A. 0.01 mg/mL
2. B. 10 mg/mL
3. C. 1 mg/mL
4. D. 0.1 mg/mL
Show answer
Answer: D. 0.1 mg/mL
1:10,000 = 1 g in 10,000 mL = 0.1 mg/mL (1 mg in 10 mL).
Magnesium sulfate 2 g is mixed in 100 mL of saline to run over 15 minutes. What pump rate is needed?
1. A. 6.7 mL/hr
2. B. 400 mL/hr
3. C. 150 mL/hr
4. D. 100 mL/hr
Show answer
Answer: B. 400 mL/hr
100 mL / 15 min = 6.67 mL/min, and 6.67 x 60 = 400 mL/hr. 6.7 mL/hr is the per-minute volume mislabeled as hourly, 150 mL/hr would take 40 minutes, and 100 mL/hr would take an hour.
D50W (50% dextrose) contains:
1. A. 50 g per 100 mL
2. B. 500 g per 100 mL
3. C. 50 mg per 100 mL
4. D. 5 g per 100 mL
Show answer
Answer: A. 50 g per 100 mL
A 50-mL amp of D50 = 25 g dextrose. That is 0.5 g/mL.
D10W contains how many grams of dextrose per 250 mL?
1. A. 100 g
2. B. 25 g
3. C. 50 g
4. D. 10 g
Show answer
Answer: B. 25 g
10% = 10 g/100 mL; 250 mL = 25 g.
An 80-kg adult with septic shock is to receive 30 mL/kg of crystalloid in boluses. What is the total volume?
1. A. 240 mL
2. B. 2,400 mL
3. C. 1,200 mL
4. D. 3,000 mL
Show answer
Answer: B. 2,400 mL
80 kg x 30 mL/kg = 2,400 mL, given in boluses with reassessment for crackles or worsening breathing. 240 mL is a decimal error, 1,200 mL uses 15 mL/kg, and 3,000 mL uses 100 kg.
Order: 0.01 mg/kg epinephrine for a 20-kg child. Dose:
1. A. 0.02 mg
2. B. 2 mg
3. C. 0.002 mg
4. D. 0.2 mg
Show answer
Answer: D. 0.2 mg
0.01 × 20 = 0.2 mg.
Order: 0.2 mg epinephrine (1:10,000) for a child. Volume:
1. A. 0.02 mL
2. B. 20 mL
3. C. 0.2 mL
4. D. 2 mL
Show answer
Answer: D. 2 mL
0.1 mg/mL; 0.2 ÷ 0.1 = 2 mL.
Order: 20 mL/kg fluid bolus for a 15-kg child. Volume:
1. A. 200 mL
2. B. 300 mL
3. C. 400 mL
4. D. 150 mL
Show answer
Answer: B. 300 mL
20 × 15 = 300 mL.
Order: 0.5 g/kg dextrose for a 10-kg infant using D10W. Volume:
1. A. 5 mL
2. B. 25 mL
3. C. 50 mL
4. D. 100 mL
Show answer
Answer: C. 50 mL
5 g needed; D10 = 0.1 g/mL; 5 ÷ 0.1 = 50 mL (= 5 mL/kg).
Order: 1 mg/kg lidocaine for an 80-kg patient. Dose:
1. A. 8 mg
2. B. 160 mg
3. C. 40 mg
4. D. 80 mg
Show answer
Answer: D. 80 mg
1 × 80 = 80 mg.
Order: 1 mcg/kg fentanyl for a 60-kg patient. Dose:
1. A. 60 mcg
2. B. 6 mcg
3. C. 0.6 mcg
4. D. 600 mcg
Show answer
Answer: A. 60 mcg
1 × 60 = 60 mcg.
Fentanyl 50 mcg/mL on hand; dose ordered 75 mcg. Volume:
1. A. 2 mL
2. B. 1.5 mL
3. C. 3 mL
4. D. 0.75 mL
Show answer
Answer: B. 1.5 mL
75 ÷ 50 = 1.5 mL.
Order: 0.1 mg/kg midazolam for a 25-kg child, max 5 mg. Dose:
1. A. 25 mg
2. B. 2.5 mg
3. C. 0.25 mg
4. D. 5 mg
Show answer
Answer: B. 2.5 mg
0.1 × 25 = 2.5 mg (under the max).
Infuse 300 mL over 90 minutes with a 15 gtt/mL set. Drip rate:
1. A. 50 gtt/min
2. B. 33 gtt/min
3. C. 200 gtt/min
4. D. 3 gtt/min
Show answer
Answer: A. 50 gtt/min
300 mL x 15 gtt/mL / 90 min = 50 gtt/min. 33 gtt/min uses a 10 gtt/mL set, 200 gtt/min uses a 60 gtt/mL set, and 3 gtt/min forgets the drop factor (3.3 mL/min).
IV drip: 250 mL over 30 minutes with a 10 gtt/mL set. Drip rate:
1. A. 83 gtt/min
2. B. 42 gtt/min
3. C. 125 gtt/min
4. D. 250 gtt/min
Show answer
Answer: A. 83 gtt/min
250 ÷ 30 = 8.33 mL/min × 10 = 83 gtt/min.
Using a 60 gtt/mL microdrip set, gtt/min equals:
1. A. mL/hr ÷ 60
2. B. mL/hr
3. C. mL/hr × 60
4. D. mL/min
Show answer
Answer: B. mL/hr
With a 60-gtt set, drops per minute = mL per hour.
Order: 100 mL over 20 minutes with a 60 gtt/mL set. Drip rate:
1. A. 100 gtt/min
2. B. 5 gtt/min
3. C. 300 gtt/min
4. D. 200 gtt/min
Show answer
Answer: C. 300 gtt/min
100 ÷ 20 = 5 mL/min × 60 = 300 gtt/min.
Dopamine 400 mg in 250 mL. Concentration in mcg/mL:
1. A. 16,000 mcg/mL
2. B. 16 mcg/mL
3. C. 160 mcg/mL
4. D. 1,600 mcg/mL
Show answer
Answer: D. 1,600 mcg/mL
400 mg = 400,000 mcg ÷ 250 = 1,600 mcg/mL.
Dopamine 1,600 mcg/mL is running at 150 mL/hr in a 75-kg patient. What dose is the patient receiving?
1. A. About 5 mcg/kg/min
2. B. About 3,200 mcg/kg/min
3. C. About 53 mcg/kg/min
4. D. About 0.9 mcg/kg/min
Show answer
Answer: C. About 53 mcg/kg/min
150 mL/hr / 60 = 2.5 mL/min; x 1,600 mcg/mL = 4,000 mcg/min; / 75 kg = about 53 mcg/kg/min, far above the usual 2 to 20 mcg/kg/min range, which suggests the rate was entered as 150 instead of 15. About 5 mcg/kg/min would be 15 mL/hr, about 3,200 forgets to divide by 60, and about 0.9 divides by 60 twice.
A double-strength bag of norepinephrine contains 8 mg in 250 mL. What is its concentration?
1. A. 16 mcg/mL
2. B. 3.2 mcg/mL
3. C. 320 mcg/mL
4. D. 32 mcg/mL
Show answer
Answer: D. 32 mcg/mL
8 mg = 8,000 mcg, and 8,000 / 250 mL = 32 mcg/mL, twice the standard 4 mg in 250 mL bag (16 mcg/mL). Setting the pump as if it were 16 mcg/mL would deliver double the intended dose; 3.2 and 320 mcg/mL are decimal errors.
Norepinephrine at 8 mcg/min using 16 mcg/mL. Rate in mL/hr:
1. A. 8 mL/hr
2. B. 30 mL/hr
3. C. 15 mL/hr
4. D. 60 mL/hr
Show answer
Answer: B. 30 mL/hr
8 ÷ 16 = 0.5 mL/min × 60 = 30 mL/hr.
An amiodarone maintenance infusion of 1 mg/min is mixed as 900 mg in 500 mL (1.8 mg/mL). What pump rate is needed?
1. A. 60 mL/hr
2. B. 33 mL/hr
3. C. 108 mL/hr
4. D. 0.6 mL/hr
Show answer
Answer: B. 33 mL/hr
1 mg/min / 1.8 mg/mL = 0.56 mL/min, and 0.56 x 60 = about 33 mL/hr, the labeled rate for the first 6-hour maintenance phase. 60 mL/hr treats the bag as 1 mg/mL, 108 mL/hr multiplies by 1.8 instead of dividing, and 0.6 mL/hr is the per-minute volume.
Lidocaine 2 g in 500 mL = ___ mg/mL:
1. A. 40 mg/mL
2. B. 4 mg/mL
3. C. 2 mg/mL
4. D. 20 mg/mL
Show answer
Answer: B. 4 mg/mL
2,000 mg ÷ 500 = 4 mg/mL.
Lidocaine infusion at 2 mg/min using 4 mg/mL with a 60-gtt set. Drip rate:
1. A. 15 gtt/min
2. B. 120 gtt/min
3. C. 30 gtt/min
4. D. 60 gtt/min
Show answer
Answer: C. 30 gtt/min
2 ÷ 4 = 0.5 mL/min × 60 = 30 gtt/min.
Convert 98.6°F to Celsius:
1. A. 35°C
2. B. 39°C
3. C. 37°C
4. D. 40°C
Show answer
Answer: C. 37°C
(98.6 − 32) × 5/9 = 37°C.
Convert 40°C to Fahrenheit:
1. A. 102°F
2. B. 106°F
3. C. 104°F
4. D. 100°F
Show answer
Answer: C. 104°F
40 × 9/5 + 32 = 104°F.
A patient weighs 100 kg. Their weight in pounds is:
1. A. 150 lb
2. B. 250 lb
3. C. 220 lb
4. D. 200 lb
Show answer
Answer: C. 220 lb
100 × 2.2 = 220 lb.
A 10-kg infant needs sodium bicarbonate 1 mEq/kg using the 4.2% solution (0.5 mEq/mL). What volume do you give?
1. A. 10 mL
2. B. 20 mL
3. C. 5 mL
4. D. 2 mL
Show answer
Answer: B. 20 mL
10 kg x 1 mEq/kg = 10 mEq, and 10 mEq / 0.5 mEq/mL = 20 mL. 10 mL assumes the adult 8.4% strength (1 mEq/mL), 5 mL multiplies by 0.5 instead of dividing, and 2 mL is a decimal error.
A nitroglycerin infusion (200 mcg/mL) runs at 6 mL/hr. You are ordered to increase the dose by 10 mcg/min. What is the new rate?
1. A. 9 mL/hr
2. B. 16 mL/hr
3. C. 3 mL/hr
4. D. 90 mL/hr
Show answer
Answer: A. 9 mL/hr
At 200 mcg/mL, 6 mL/hr delivers 20 mcg/min (6 x 200 / 60). Raising it to 30 mcg/min needs 30 / 200 x 60 = 9 mL/hr. 16 mL/hr adds 10 to the mL/hr instead of the mcg/min, 3 mL/hr is the size of the increase alone, and 90 mL/hr is a decimal error.
Order: midazolam 0.05 mg/kg IV for a 13-kg child. On hand: 1 mg/mL. Volume:
1. A. 6.5 mL
2. B. 0.065 mL
3. C. 0.65 mL
4. D. 1.3 mL
Show answer
Answer: C. 0.65 mL
13 kg x 0.05 mg/kg = 0.65 mg; at 1 mg/mL that is 0.65 mL, best measured in a 1-mL syringe. 6.5 mL and 0.065 mL are decimal errors, and 1.3 mL uses 0.1 mg/kg.
The formula 'volume × drop factor ÷ time (min)' calculates:
1. A. Volume to administer
2. B. Drip rate in gtt/min
3. C. Concentration in mg/mL
4. D. Total dose in mg
Show answer
Answer: B. Drip rate in gtt/min
Standard IV drip calculation.
Order: 1 g calcium chloride (10% solution). Volume:
1. A. 5 mL
2. B. 100 mL
3. C. 1 mL
4. D. 10 mL
Show answer
Answer: D. 10 mL
10% = 100 mg/mL; 1,000 ÷ 100 = 10 mL.
An 18-kg child in hyperkalemic arrest needs calcium chloride 20 mg/kg. The 10% solution contains 100 mg/mL. What volume do you give?
1. A. 3.6 mL
2. B. 36 mL
3. C. 0.36 mL
4. D. 1.8 mL
Show answer
Answer: A. 3.6 mL
18 kg x 20 mg/kg = 360 mg, and 360 mg / 100 mg/mL = 3.6 mL, pushed slowly through a large, secure line because calcium chloride is irritating to veins. 36 mL and 0.36 mL are tenfold decimal errors, and 1.8 mL uses 10 mg/kg.
Sodium bicarbonate 8.4% contains:
1. A. 8.4 mg/mL
2. B. 84 mg/mL
3. C. 0.84 mg/mL
4. D. 840 mg/mL
Show answer
Answer: B. 84 mg/mL
8.4 g/100 mL = 84 mg/mL = 1 mEq/mL.
Order: 1 mEq/kg sodium bicarbonate for a 70-kg patient using 8.4%. Volume:
1. A. 7 mL
2. B. 35 mL
3. C. 70 mL
4. D. 140 mL
Show answer
Answer: C. 70 mL
70 mEq ÷ 1 mEq/mL = 70 mL.
Order: atropine 0.02 mg/kg for a 15-kg child. Dose:
1. A. 0.5 mg
2. B. 0.1 mg
3. C. 1 mg
4. D. 0.3 mg
Show answer
Answer: D. 0.3 mg
0.02 mg/kg x 15 kg = 0.3 mg, below the 0.5-mg maximum single dose. Current PALS guidance no longer uses a 0.1-mg minimum dose. 0.1 mg and 0.5 mg are not the calculated dose, and 1 mg exceeds the pediatric single-dose maximum.
Atropine 0.3 mg from 0.1 mg/mL (1 mg/10 mL). Volume:
1. A. 3 mL
2. B. 0.03 mL
3. C. 30 mL
4. D. 0.3 mL
Show answer
Answer: A. 3 mL
0.3 ÷ 0.1 = 3 mL.
Order: 2 mg/kg ketamine IM for a 50-kg patient. Dose:
1. A. 100 mg
2. B. 200 mg
3. C. 50 mg
4. D. 10 mg
Show answer
Answer: A. 100 mg
2 × 50 = 100 mg.
Ketamine 50 mg/mL on hand; 100 mg ordered. Volume:
1. A. 0.5 mL
2. B. 1 mL
3. C. 4 mL
4. D. 2 mL
Show answer
Answer: D. 2 mL
100 ÷ 50 = 2 mL.
Naloxone 0.4 mg from a 2 mg/2 mL syringe (1 mg/mL). Volume:
1. A. 0.4 mL
2. B. 0.2 mL
3. C. 0.8 mL
4. D. 4 mL
Show answer
Answer: A. 0.4 mL
0.4 ÷ 1 = 0.4 mL.
Order: 324 mg chewable aspirin from 81-mg tablets. Number of tablets:
1. A. 3
2. B. 2
3. C. 4
4. D. 5
Show answer
Answer: C. 4
324 ÷ 81 = 4 tablets.
Diphenhydramine 50 mg/mL on hand; order 25 mg. Volume:
1. A. 0.5 mL
2. B. 1 mL
3. C. 2 mL
4. D. 0.25 mL
Show answer
Answer: A. 0.5 mL
25 ÷ 50 = 0.5 mL.
A 12-kg child is to receive a 20-mL/kg bolus, and the pump is set at 1,440 mL/hr. About how long will the bolus take?
1. A. 1 minute
2. B. 10 minutes
3. C. 20 minutes
4. D. 60 minutes
Show answer
Answer: B. 10 minutes
12 kg x 20 mL/kg = 240 mL, and 240 / 1,440 mL/hr = 0.167 hr, or 10 minutes. 20 minutes would deliver 480 mL (40 mL/kg), 60 minutes would deliver 1,440 mL, and 1 minute would deliver only 24 mL.
Infusion running at 50 gtt/min with a 10-gtt set delivers how many mL/hr?
1. A. 5 mL/hr
2. B. 3,000 mL/hr
3. C. 300 mL/hr
4. D. 50 mL/hr
Show answer
Answer: C. 300 mL/hr
50 ÷ 10 = 5 mL/min × 60 = 300 mL/hr.
Epinephrine push-dose: 1 mL of 0.1 mg/mL diluted to 10 mL gives:
1. A. 1 mg/mL
2. B. 1 mcg/mL
3. C. 10 mcg/mL
4. D. 0.1 mg/mL
Show answer
Answer: C. 10 mcg/mL
100 mcg in 10 mL = 10 mcg/mL.
A length-based tape estimates a child's weight at 12 kg. Epinephrine 0.01 mg/kg dose:
1. A. 1.2 mg
2. B. 0.0012 mg
3. C. 0.012 mg
4. D. 0.12 mg
Show answer
Answer: D. 0.12 mg
0.01 × 12 = 0.12 mg.
Ratio-proportion method: 10 mg : 2 mL = 15 mg : X. X equals:
1. A. 1 mL
2. B. 4 mL
3. C. 3 mL
4. D. 2 mL
Show answer
Answer: C. 3 mL
Cross-multiply: 10X = 30, X = 3 mL.
The metric prefix 'kilo' means:
1. A. 1/1,000
2. B. 100
3. C. 1,000
4. D. 1/100
Show answer
Answer: C. 1,000
Kilo = thousand.
The metric prefix 'micro' means:
1. A. 1/1,000,000
2. B. 1,000,000
3. C. 1/1,000
4. D. 1/1,000,000,000
Show answer
Answer: A. 1/1,000,000
Micro = one millionth.
Convert 0.75 L to mL:
1. A. 750 mL
2. B. 7.5 mL
3. C. 75 mL
4. D. 7,500 mL
Show answer
Answer: A. 750 mL
0.75 × 1,000 = 750 mL.
Convert 1,250 mL to L:
1. A. 125 L
2. B. 1.25 L
3. C. 0.125 L
4. D. 12.5 L
Show answer
Answer: B. 1.25 L
1,250 ÷ 1,000 = 1.25 L.
Which action best prevents calculation errors under stress?
1. A. Rounding all doses up to whole numbers
2. B. Skipping the math and using usual volumes
3. C. Writing it down and having it verified
4. D. Doing the math in your head quickly
Show answer
Answer: C. Writing it down and having it verified
Write the calculation down, use a reference, and have a partner verify it. Written, verified calculations reduce decimal and unit errors.
Order: midazolam 2.5 mg IV. On hand: 5 mg/mL. Volume to draw up:
1. A. 2 mL
2. B. 0.5 mL
3. C. 0.25 mL
4. D. 5 mL
Show answer
Answer: B. 0.5 mL
2.5 mg ÷ 5 mg × 1 mL = 0.5 mL.
Order: fentanyl 50 mcg IV. On hand: 100 mcg in 2 mL. Volume to administer:
1. A. 2 mL
2. B. 1 mL
3. C. 0.5 mL
4. D. 4 mL
Show answer
Answer: B. 1 mL
50 mcg ÷ 100 mcg × 2 mL = 1 mL.
Order: adenosine 6 mg rapid IV push. On hand: 3 mg/mL. Volume:
1. A. 3 mL
2. B. 0.5 mL
3. C. 18 mL
4. D. 2 mL
Show answer
Answer: D. 2 mL
6 mg ÷ 3 mg × 1 mL = 2 mL.
Order: morphine 4 mg IV. On hand: 10 mg/mL. Volume:
1. A. 0.4 mL
2. B. 0.04 mL
3. C. 4 mL
4. D. 2.5 mL
Show answer
Answer: A. 0.4 mL
4 mg ÷ 10 mg × 1 mL = 0.4 mL.
Order: ketorolac 15 mg IV. On hand: 30 mg/mL. Volume:
1. A. 2 mL
2. B. 0.2 mL
3. C. 1.5 mL
4. D. 0.5 mL
Show answer
Answer: D. 0.5 mL
15 mg ÷ 30 mg × 1 mL = 0.5 mL.
Order: lorazepam 2 mg IV. On hand: 4 mg/mL. Volume:
1. A. 0.5 mL
2. B. 2 mL
3. C. 1 mL
4. D. 0.2 mL
Show answer
Answer: A. 0.5 mL
2 mg ÷ 4 mg × 1 mL = 0.5 mL.
Order: methylprednisolone 60 mg IV. The reconstituted vial contains 125 mg in 2 mL. Volume:
1. A. 0.96 mL
2. B. 4.17 mL
3. C. 2.08 mL
4. D. 0.48 mL
Show answer
Answer: A. 0.96 mL
60 mg ÷ 125 mg × 2 mL = 0.96 mL.
How many milliliters of D10 provide the same 25 g of dextrose as one 50-mL syringe of D50?
1. A. 125 mL
2. B. 50 mL
3. C. 250 mL
4. D. 500 mL
Show answer
Answer: C. 250 mL
D10 contains 10 g per 100 mL (0.1 g/mL), so 25 g / 0.1 g/mL = 250 mL. 125 mL delivers 12.5 g, 50 mL delivers 5 g, and 500 mL delivers 50 g. Many systems give D10 in 50- to 100-mL steps and recheck glucose instead of a full 250 mL at once.
Order: dextrose 10 g IV. On hand: D10W. Volume:
1. A. 10 mL
2. B. 50 mL
3. C. 1,000 mL
4. D. 100 mL
Show answer
Answer: D. 100 mL
D10W = 10 g/100 mL = 0.1 g/mL; 10 g ÷ 0.1 g/mL = 100 mL.
Glucagon 1 mg is reconstituted with 1 mL of diluent. Order: 0.5 mg IM for a small child. Volume:
1. A. 2 mL
2. B. 1 mL
3. C. 0.05 mL
4. D. 0.5 mL
Show answer
Answer: D. 0.5 mL
0.5 mg ÷ 1 mg × 1 mL = 0.5 mL.
Order: ondansetron 2 mg IV. A vial contains 4 mg in 2 mL (2 mg/mL). Volume:
1. A. 4 mL
2. B. 1 mL
3. C. 2 mL
4. D. 0.5 mL
Show answer
Answer: B. 1 mL
4 mg/2 mL = 2 mg/mL; 2 mg ÷ 2 mg/mL = 1 mL.
Order: ketamine 1 mg/kg IV for a 154-lb patient. Dose:
1. A. 154 mg
2. B. 70 mg
3. C. 35 mg
4. D. 7 mg
Show answer
Answer: B. 70 mg
154 lb ÷ 2.2 = 70 kg; 70 kg × 1 mg/kg = 70 mg. Using pounds gives 154 mg.
Order: ondansetron 0.15 mg/kg IV for a 33-lb child. Dose:
1. A. 22.5 mg
2. B. 4.95 mg
3. C. 0.225 mg
4. D. 2.25 mg
Show answer
Answer: D. 2.25 mg
33 lb ÷ 2.2 = 15 kg; 15 × 0.15 mg/kg = 2.25 mg. Using pounds gives 4.95 mg.
Order: fentanyl 1.5 mcg/kg IN for a 22-kg child. Dose:
1. A. 330 mcg
2. B. 14.7 mcg
3. C. 33 mcg
4. D. 3.3 mcg
Show answer
Answer: C. 33 mcg
22 kg × 1.5 mcg/kg = 33 mcg.
Order: amiodarone 5 mg/kg IV/IO for an 18-kg child in pulseless VF. Dose:
1. A. 180 mg
2. B. 9 mg
3. C. 90 mg
4. D. 900 mg
Show answer
Answer: C. 90 mg
18 kg × 5 mg/kg = 90 mg.
Order: adenosine 0.1 mg/kg rapid IV for a 14-kg child in SVT. Dose:
1. A. 0.7 mg
2. B. 14 mg
3. C. 0.14 mg
4. D. 1.4 mg
Show answer
Answer: D. 1.4 mg
14 kg × 0.1 mg/kg = 1.4 mg.
Order: epinephrine 0.01 mg/kg IM for a 30-kg child in anaphylaxis. On hand: 1 mg/mL. Volume:
1. A. 0.3 mL
2. B. 3 mL
3. C. 0.03 mL
4. D. 0.15 mL
Show answer
Answer: A. 0.3 mL
30 kg × 0.01 mg/kg = 0.3 mg; 0.3 mg ÷ 1 mg/mL = 0.3 mL. 3 mL would result from mistakenly using 0.1 mg/mL.
Order: diphenhydramine 1 mg/kg IV for a 66-lb child. Dose:
1. A. 66 mg
2. B. 3 mg
3. C. 15 mg
4. D. 30 mg
Show answer
Answer: D. 30 mg
66 lb ÷ 2.2 = 30 kg; 30 kg × 1 mg/kg = 30 mg.
Order: naloxone 0.1 mg/kg for an 8-kg infant. Dose:
1. A. 0.4 mg
2. B. 0.8 mg
3. C. 0.08 mg
4. D. 8 mg
Show answer
Answer: B. 0.8 mg
8 kg × 0.1 mg/kg = 0.8 mg.
Order: midazolam 0.2 mg/kg IN for a 20-kg seizing child. On hand: 5 mg/mL. Volume:
1. A. 8 mL
2. B. 0.8 mL
3. C. 4 mL
4. D. 0.4 mL
Show answer
Answer: B. 0.8 mL
20 kg × 0.2 mg/kg = 4 mg; 4 mg ÷ 5 mg/mL = 0.8 mL.
A 16-kg child receives D10W at 5 mL/kg. How many grams of dextrose are delivered?
1. A. 80 g
2. B. 8 g
3. C. 0.8 g
4. D. 16 g
Show answer
Answer: B. 8 g
16 kg × 5 mL/kg = 80 mL; 80 mL × 0.1 g/mL = 8 g.
Order: 20 mL/kg normal saline bolus for a 55-lb child. Volume:
1. A. 250 mL
2. B. 500 mL
3. C. 1,100 mL
4. D. 50 mL
Show answer
Answer: B. 500 mL
55 lb ÷ 2.2 = 25 kg; 25 kg × 20 mL/kg = 500 mL. Using pounds gives 1,100 mL.
Order: 10 mL/kg normal saline for a 3.5-kg newborn. Volume:
1. A. 350 mL
2. B. 70 mL
3. C. 3.5 mL
4. D. 35 mL
Show answer
Answer: D. 35 mL
3.5 kg × 10 mL/kg = 35 mL.
Order: magnesium sulfate 50 mg/kg IV for a 20-kg child with severe asthma. Dose:
1. A. 1,000 mg
2. B. 100 mg
3. C. 2,500 mg
4. D. 10,000 mg
Show answer
Answer: A. 1,000 mg
20 kg × 50 mg/kg = 1,000 mg (1 g), below the usual 2 g maximum.
A 154-lb adult is ordered 20 mL/kg of saline, to a maximum of 1,000 mL. What volume do you give?
1. A. 1,400 mL
2. B. 3,080 mL
3. C. 1,000 mL
4. D. 700 mL
Show answer
Answer: C. 1,000 mL
154 lb / 2.2 = 70 kg, and 70 x 20 = 1,400 mL, which exceeds the 1,000-mL cap, so give 1,000 mL and reassess. 1,400 mL ignores the cap, 3,080 mL multiplies by pounds, and 700 mL uses 10 mL/kg.
A patient weighs 187 lb. Weight in kilograms:
1. A. 18.7 kg
2. B. 411.4 kg
3. C. 85 kg
4. D. 93.5 kg
Show answer
Answer: C. 85 kg
187 ÷ 2.2 = 85 kg.
An infant weighs 5 kg. Weight in pounds:
1. A. 25 lb
2. B. 11 lb
3. C. 7.2 lb
4. D. 2.3 lb
Show answer
Answer: B. 11 lb
5 kg × 2.2 = 11 lb.
A patient weighs 68 kg. Weight in pounds (nearest whole number):
1. A. 150 lb
2. B. 31 lb
3. C. 136 lb
4. D. 170 lb
Show answer
Answer: A. 150 lb
68 × 2.2 = 149.6, about 150 lb.
Infuse 1,000 mL over 6 hours with a 10 gtt/mL set. Drip rate:
1. A. 17 gtt/min
2. B. 28 gtt/min
3. C. 167 gtt/min
4. D. 42 gtt/min
Show answer
Answer: B. 28 gtt/min
1,000 mL × 10 gtt/mL ÷ 360 min = 27.7778, about 28 gtt/min.
Infuse 500 mL over 2 hours with a 15 gtt/mL set. Drip rate:
1. A. 250 gtt/min
2. B. 63 gtt/min
3. C. 42 gtt/min
4. D. 31 gtt/min
Show answer
Answer: B. 63 gtt/min
500 mL × 15 gtt/mL ÷ 120 min = 62.5, about 63 gtt/min.
Infuse 200 mL over 30 minutes with a 10 gtt/mL set. Drip rate:
1. A. 67 gtt/min
2. B. 400 gtt/min
3. C. 7 gtt/min
4. D. 100 gtt/min
Show answer
Answer: A. 67 gtt/min
200 mL × 10 gtt/mL ÷ 30 min = 66.6667, about 67 gtt/min.
Infuse 750 mL over 3 hours with a 10 gtt/mL set. Drip rate:
1. A. 63 gtt/min
2. B. 250 gtt/min
3. C. 42 gtt/min
4. D. 4 gtt/min
Show answer
Answer: C. 42 gtt/min
750 mL × 10 gtt/mL ÷ 180 min = 41.6667, about 42 gtt/min.
Infuse 50 mL over 15 minutes with a 60 gtt/mL set. Drip rate:
1. A. 33 gtt/min
2. B. 3 gtt/min
3. C. 50 gtt/min
4. D. 200 gtt/min
Show answer
Answer: D. 200 gtt/min
50 mL × 60 gtt/mL ÷ 15 min = 200 gtt/min.
A microdrip set (60 gtt/mL) is running at 45 gtt/min. How long will it take to infuse 90 mL?
1. A. 2 hours
2. B. 2 minutes
3. C. 45 minutes
4. D. 4 hours
Show answer
Answer: A. 2 hours
With a 60 gtt/mL set, drops per minute equal mL per hour, so 45 gtt/min = 45 mL/hr, and 90 mL / 45 mL/hr = 2 hours. 2 minutes treats the drops as milliliters per minute, 45 minutes confuses the drip rate with time, and 4 hours assumes half the rate.
Infuse 1,000 mL over 8 hours with a 10 gtt/mL set. Drip rate:
1. A. 208 gtt/min
2. B. 125 gtt/min
3. C. 31 gtt/min
4. D. 21 gtt/min
Show answer
Answer: D. 21 gtt/min
1,000 mL × 10 gtt/mL ÷ 480 min = 20.8333, about 21 gtt/min.
An IV is dripping at 30 gtt/min through a 15 gtt/mL set. Hourly volume:
1. A. 450 mL/hr
2. B. 2 mL/hr
3. C. 120 mL/hr
4. D. 180 mL/hr
Show answer
Answer: C. 120 mL/hr
30 gtt/min ÷ 15 gtt/mL = 2 mL/min; 2 × 60 = 120 mL/hr.
An IV is dripping at 21 gtt/min through a 10 gtt/mL set. Volume infused in 1 hour:
1. A. 1,260 mL
2. B. 210 mL
3. C. 126 mL
4. D. 84 mL
Show answer
Answer: C. 126 mL
21 ÷ 10 = 2.1 mL/min; 2.1 × 60 = 126 mL.
A 500-mL bag runs at 100 mL/hr. How long will it last?
1. A. 50 hours
2. B. 8 hours
3. C. 0.5 hours
4. D. 5 hours
Show answer
Answer: D. 5 hours
500 mL ÷ 100 mL/hr = 5 hours.
An IV is ordered at 30 mL/hr to keep the vein open, using a 10 gtt/mL set. Drip rate:
1. A. 5 gtt/min
2. B. 30 gtt/min
3. C. 3 gtt/min
4. D. 50 gtt/min
Show answer
Answer: A. 5 gtt/min
30 mL/hr / 60 = 0.5 mL/min, and 0.5 x 10 gtt/mL = 5 gtt/min (about one drop every 12 seconds). 30 gtt/min would be correct only for a 60 gtt/mL set, 3 gtt/min divides mL/hr by the drop factor, and 50 gtt/min is a decimal error.
Dopamine 10 mcg/kg/min for a 70-kg patient; concentration 1,600 mcg/mL. Rate (nearest mL/hr):
1. A. 44 mL/hr
2. B. 53 mL/hr
3. C. 4 mL/hr
4. D. 26 mL/hr
Show answer
Answer: D. 26 mL/hr
10 × 70 = 700 mcg/min; 700 ÷ 1,600 = 0.4375 mL/min; × 60 = 26.25, about 26 mL/hr.
Dobutamine 250 mg in 250 mL (1,000 mcg/mL) at 5 mcg/kg/min for a 60-kg patient. Rate:
1. A. 300 mL/hr
2. B. 0.3 mL/hr
3. C. 30 mL/hr
4. D. 18 mL/hr
Show answer
Answer: D. 18 mL/hr
5 × 60 = 300 mcg/min; 300 ÷ 1,000 = 0.3 mL/min; × 60 = 18 mL/hr.
Norepinephrine 4 mg in 250 mL at 0.05 mcg/kg/min for a 96-kg patient. Rate:
1. A. 30 mL/hr
2. B. 18 mL/hr
3. C. 0.3 mL/hr
4. D. 180 mL/hr
Show answer
Answer: B. 18 mL/hr
4,000 mcg ÷ 250 mL = 16 mcg/mL; 0.05 × 96 = 4.8 mcg/min; 4.8 ÷ 16 × 60 = 18 mL/hr.
Epinephrine 1 mg in 250 mL at 2 mcg/min. Rate through a 60 gtt/mL set:
1. A. 30 gtt/min
2. B. 120 gtt/min
3. C. 0.5 gtt/min
4. D. 8 gtt/min
Show answer
Answer: A. 30 gtt/min
1,000 mcg ÷ 250 mL = 4 mcg/mL; 2 ÷ 4 = 0.5 mL/min; × 60 = 30 gtt/min (microdrip).
Dobutamine 500 mg is added to 250 mL. Concentration:
1. A. 200 mcg/mL
2. B. 20,000 mcg/mL
3. C. 2,000 mcg/mL
4. D. 2 mcg/mL
Show answer
Answer: C. 2,000 mcg/mL
500 mg × 1,000 = 500,000 mcg ÷ 250 mL = 2,000 mcg/mL.
Norepinephrine 16 mcg/mL is running at 45 mL/hr. How many mcg/min is the patient receiving?
1. A. 12 mcg/min
2. B. 720 mcg/min
3. C. 2.8 mcg/min
4. D. 45 mcg/min
Show answer
Answer: A. 12 mcg/min
45 mL/hr x 16 mcg/mL = 720 mcg/hr, and 720 / 60 = 12 mcg/min. 720 mcg/min forgets to divide by 60, 2.8 mcg/min divides 45 by 16, and 45 mcg/min confuses mL/hr with mcg/min.
Nitroglycerin 50 mg in 250 mL at 20 mcg/min. Rate:
1. A. 10 mL/hr
2. B. 60 mL/hr
3. C. 0.1 mL/hr
4. D. 6 mL/hr
Show answer
Answer: D. 6 mL/hr
50,000 mcg ÷ 250 mL = 200 mcg/mL; 20 ÷ 200 = 0.1 mL/min; × 60 = 6 mL/hr.
A 1% lidocaine solution contains:
1. A. 100 mg/mL
2. B. 1 mg/mL
3. C. 10 mg/mL
4. D. 0.1 mg/mL
Show answer
Answer: C. 10 mg/mL
1% = 1 g/100 mL = 1,000 mg/100 mL = 10 mg/mL.
How many milligrams of lidocaine are in 5 mL of a 2% solution?
1. A. 100 mg
2. B. 1,000 mg
3. C. 10 mg
4. D. 40 mg
Show answer
Answer: A. 100 mg
2% = 20 mg/mL; 5 mL × 20 mg/mL = 100 mg.
How many milligrams of calcium gluconate are in 10 mL of a 10% solution?
1. A. 100 mg
2. B. 1,000 mg
3. C. 10,000 mg
4. D. 10 mg
Show answer
Answer: B. 1,000 mg
10% = 100 mg/mL; 10 mL × 100 mg/mL = 1,000 mg (1 g).
How many grams of sodium chloride are in 1 L of 0.9% normal saline?
1. A. 0.9 g
2. B. 900 g
3. C. 90 g
4. D. 9 g
Show answer
Answer: D. 9 g
0.9 g/100 mL × 1,000 mL = 9 g.
How many grams of sodium chloride are in 250 mL of 3% saline?
1. A. 0.75 g
2. B. 3 g
3. C. 75 g
4. D. 7.5 g
Show answer
Answer: D. 7.5 g
3 g/100 mL × 250 mL = 7.5 g.
How many milligrams of epinephrine are in 0.15 mL of the 1 mg/mL (1:1,000) concentration?
1. A. 0.15 mg
2. B. 0.0015 mg
3. C. 1.5 mg
4. D. 0.015 mg
Show answer
Answer: A. 0.15 mg
1 mg/mL × 0.15 mL = 0.15 mg.
Push-dose epinephrine is mixed at 10 mcg/mL. Giving 2 mL delivers:
1. A. 5 mcg
2. B. 20 mcg
3. C. 2 mcg
4. D. 200 mcg
Show answer
Answer: B. 20 mcg
2 mL × 10 mcg/mL = 20 mcg.
D25W contains how many grams of dextrose per milliliter?
1. A. 25 g/mL
2. B. 0.025 g/mL
3. C. 2.5 g/mL
4. D. 0.25 g/mL
Show answer
Answer: D. 0.25 g/mL
25% = 25 g/100 mL = 0.25 g/mL.
Convert 0.025 mg to micrograms:
1. A. 250 mcg
2. B. 2.5 mcg
3. C. 25 mcg
4. D. 0.25 mcg
Show answer
Answer: C. 25 mcg
0.025 mg × 1,000 = 25 mcg.
Convert 1,500 mg to grams:
1. A. 15 g
2. B. 0.15 g
3. C. 150 g
4. D. 1.5 g
Show answer
Answer: D. 1.5 g
1,500 mg ÷ 1,000 = 1.5 g.
Convert 2,000 mcg to milligrams:
1. A. 20 mg
2. B. 200 mg
3. C. 0.2 mg
4. D. 2 mg
Show answer
Answer: D. 2 mg
2,000 mcg ÷ 1,000 = 2 mg.
A parent gave 2 teaspoons of liquid medication. Approximate volume:
1. A. 10 mL
2. B. 15 mL
3. C. 30 mL
4. D. 2 mL
Show answer
Answer: A. 10 mL
1 tsp ≈ 5 mL; 2 × 5 = 10 mL.
A patient drank 8 fl oz of water. Approximate volume:
1. A. 240 mL
2. B. 80 mL
3. C. 800 mL
4. D. 24 mL
Show answer
Answer: A. 240 mL
1 fl oz ≈ 30 mL; 8 × 30 = 240 mL.

Medical Math Practice Questions

139 practice questions

More Medication Administration practice questions