A solution labeled 10 mg/mL. If dose is 250 mg, how many mL are needed?

A solution labeled 10 mg/mL. If dose is 250 mg, how many mL are needed?

• A. 20 mL
• B. 10 mL
• C. 25 mL
• D. 50 mL

Answer: (C)

To find how much volume is needed, use Volume = Dose ÷ (concentration). The solution is 10 mg per mL, so 250 mg ÷ 10 mg/mL = 25 mL. A quick check: 25 mL × 10 mg/mL = 250 mg. Using 20 mL would give 200 mg, 10 mL would give 100 mg, and 50 mL would give 500 mg, so 25 mL is the correct amount.

To find how much volume is needed, use Volume = Dose ÷ (concentration). The solution is 10 mg per mL, so 250 mg ÷ 10 mg/mL = 25 mL. A quick check: 25 mL × 10 mg/mL = 250 mg. Using 20 mL would give 200 mg, 10 mL would give 100 mg, and 50 mL would give 500 mg, so 25 mL is the correct amount.