## Chapter 72. Pharmacy Calculations

Identify the Roman numeral with a value of 50.

a. X

b. M

c. I

d. L

Answer d is correct. L = 50.

Answer a is incorrect. X = 10.

Answer b is incorrect. M = 1000.

Answer c is incorrect. I = 1.

Identify the Arabic value of DCXXIV.

a. 624

b. 626

c. 1024

d. 1026

Answer a is correct. D = 500, C = 100, X = 10, I = −1, V = 5 (500 + 100 + 10 + 10 −1 +5 = 624).

Answer b is incorrect. The Roman numeral for 626 would be DCXXVI.

Answer c is incorrect. The Roman numeral for 1024 would be MXXIV.

Answer d is incorrect. The Roman numeral for 1026 would be MXXVI.

If 120 mL of a cough syrup contains 0.4 g of dextromethorphan, how many milligrams are contained in 1 teaspoonful?

a. 0.016 mg

b. 16 mg

c. 160 mg

d. 1.6 mg Alternative method using dimensional analysis: Answers a. c, and d are incorrect.

Interferon injection contains 5 million units/mL. How many units are in 0.65 mL?

a. 3,250 U

b. 32,500 U

c. 325,000 U

d. 3,250,000 U Answers a, b, and c are incorrect.

An inhalant solution contains 0.025% w/v of a drug in 5 mL. Calculate the number of Milligrams in this solution.

a. 0.125 mg

b. 1.25 mg

c. 12.5 mg

d. 0.0125 mg

Answer b is correct. 0.025 % w/v = 0.025 g/100 ...

### Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.