0.75 liter of 0.07 % is used and 0.25 liter of 0.23 % salt is used
<em><u>Solution:</u></em>
We have to 1 liter of final solution
Let "x" be the salt solution of 0.07 %
Then, (1 - x) is the salt solution of 0.23 %
Then final solution should be 1 liter of solution which contains 0.11 % salt
Thus, 0.07 % of "x" is mixed with 0.23 % of (1 - x) to make a solution 0.11 % of 1 liter
<em><u>Thus a equation is framed as:</u></em>
0.07 % of x + 0.23 % of (1 - x) = 0.11 % of 1
Thus 0.75 liter of 0.07 % is used
And,
1 - x = 1 - 0.75 = 0.25
Thus 0.25 liter of 0.23 % salt is used