Problema Solution
Nora works at a laboratory as a chemist. She was told to prepare 100L of 25% alcohol solution. she has on hand of a 15% alcohol solution which she thought of mixing. How many liters of each solution will be required to make the mixture?
Answer provided by our tutors
The problem statement is ambiguous and we assume that Nora is adding pure acid, otherwise there is no way in which "something other than 25%" is added to "15%" in order to increase the acidic percent.
So assuming, assuming, assuming [yea, okay] that pure acide is added to the 15% solution:
0.25*1000 = 0.15x + (1000-x)
x=882.35
1000-882=118
So, based on the required crazy assumptions, Nora would add approximately 118L of pure acid to the 882L of 15% acid in order to make 1000L of 25% acid.