A patient needs to be given exactly 1000ml of 15% (w/v) intravenous glucose solution. The stock solution is 35% (w/v). How many milliners of the stock solution are needed to prepare the fluid for the IV bag?

In this question, the patient needs to be given exactly 1000ml of a 15.0%. The content of the glucose should be:

weight = volume * density * concentration

1000ml * 1mg/ml * 15% = 150mg.

The stock solution is 35%, then the amount needed in ml would be:

weight = volume * density * concentration

150mg = volume * 1mg/ml * 35%

volume = 150/35% = 3000/7 = 428.5ml