A solution has 0.25 mg/mL; the dose is 6 mg; what mL?

A solution has 0.25 mg/mL; the dose is 6 mg; what mL?

• A. 24 mL
• B. 12 mL
• C. 30 mL
• D. 36 mL

Answer: (A)

When you need a certain dose from a labeled solution, use volume = dose / concentration. The concentration is 0.25 mg per mL, so each milliliter provides 0.25 mg. To deliver 6 mg, calculate 6 ÷ 0.25 = 24. This means 24 mL will contain 6 mg, since 24 mL × 0.25 mg/mL = 6 mg. Therefore, administer 24 mL.

When you need a certain dose from a labeled solution, use volume = dose / concentration. The concentration is 0.25 mg per mL, so each milliliter provides 0.25 mg. To deliver 6 mg, calculate 6 ÷ 0.25 = 24. This means 24 mL will contain 6 mg, since 24 mL × 0.25 mg/mL = 6 mg. Therefore, administer 24 mL.