Free NEX Mathematical Calculations: Dosages and Solutions Questions and Answers 1 — Questions and Answers
Question 1: A physician orders 500 mg of a medication. The medication is available in 250 mg tablets. How many tablets should the nurse administer?
- 1 tablet
- 1.5 tablets
- 2 tablets (Correct answer)
- 0.5 tablets
Correct answer: 2 tablets
To solve this, use the formula: Dose Ordered / Dose on Hand. In this case, 500 mg (ordered) divided by 250 mg (on hand) equals 2. The nurse should administer 2 tablets.
Question 2: The order is for 60 mg of a liquid medication. The pharmacy supplies the medication in a concentration of 80 mg/2 mL. How many mL should be administered?
- 1.25 mL
- 1.5 mL (Correct answer)
- 2.0 mL
- 2.67 mL
Correct answer: 1.5 mL
Use the formula: (Dose Ordered / Dose on Hand) x Quantity. This is (60 mg / 80 mg) x 2 mL. This simplifies to 0.75 x 2 mL, which equals 1.5 mL.
Question 3: An IV bag contains 1000 mL of fluid to be infused over 5 hours. At what rate in mL/hr should the nurse set the infusion pump?
- 150 mL/hr
- 175 mL/hr
- 250 mL/hr
- 200 mL/hr (Correct answer)
Correct answer: 200 mL/hr
To find the infusion rate in mL per hour, divide the total volume by the total time in hours. 1000 mL divided by 5 hours equals 200 mL/hr.
Question 4: A patient who weighs 70 kg is prescribed a medication at a dose of 3 mg/kg. What is the total dose in mg the patient should receive?
- 210 mg (Correct answer)
- 73 mg
- 23.3 mg
- 140 mg
Correct answer: 210 mg
To calculate a weight-based dose, multiply the patient's weight in kg by the prescribed dose per kg. 70 kg multiplied by 3 mg/kg equals 210 mg.
Question 5: A doctor prescribes 0.75 g of a drug. The available tablets are 250 mg each. How many tablets should be given?
- 2 tablets
- 2.5 tablets
- 3 tablets (Correct answer)
- 4 tablets
Correct answer: 3 tablets
First, convert the prescribed dose to the same unit as the available tablets. Since 1 g = 1000 mg, 0.75 g is equal to 750 mg. Then, divide the ordered dose (750 mg) by the dose on hand (250 mg), which equals 3 tablets.
Question 6: How many grams of dextrose are in 500 mL of a 5% Dextrose in Water (D5W) solution?
- 5 g
- 25 g (Correct answer)
- 50 g
- 10 g
Correct answer: 25 g
A 5% solution means there are 5 grams of solute for every 100 mL of solution. To find the amount in 500 mL, set up a proportion: (5 g / 100 mL) = (x g / 500 mL). Solving for x gives (5 * 500) / 100 = 25 grams.
Free NEX Mathematical Calculations: Dosages and Solutions Questions and Answers 1
A physician orders 500 mg of a medication.
The medication is available in 250 mg tablets.
How many tablets should the nurse administer?