In the 50 mL final dilution scenario, if 1 mL of drug solution is added, how many milliliters of diluent are needed to reach the final volume?

In the 50 mL final dilution scenario, if 1 mL of drug solution is added, how many milliliters of diluent are needed to reach the final volume?

• A. 50 mL
• B. 25 mL
• C. 1 mL
• D. 49 mL

Answer: (D)

The final volume equals the sum of what you add and the diluent you add. If you have 1 mL of drug solution and you want a final volume of 50 mL, you need enough diluent to bring the total to 50 mL. That means 50 mL − 1 mL = 49 mL of diluent. So 49 mL is required to reach the 50 mL final volume. Adding more or less diluent would give a final volume other than 50 mL.

The final volume equals the sum of what you add and the diluent you add. If you have 1 mL of drug solution and you want a final volume of 50 mL, you need enough diluent to bring the total to 50 mL. That means 50 mL − 1 mL = 49 mL of diluent. So 49 mL is required to reach the 50 mL final volume. Adding more or less diluent would give a final volume other than 50 mL.