Question 1095956
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<pre>
Let x be the volume of the 50% solution, in liters.

Then the volume of the 80% solution is (20-x) liters (since you want to have 20 liters of the resulting solution).


The pure antiseptic volume in the mixture will be  

0.5x + 0.8*(20-x),

with each addend from the corresponding input ingredient.


Then the percentage equation ("concentration") will be

{{{(0.5x + 0.8*(20-x))/20}}} = 0.7        (<<<---=== 70% resulting solution).


Solve it step by step:

0.5x + 0.8*20 - 0.8x = 0.7*20

-0.3x = 0.7*20 - 0.8*20 = -0.1*20 = -2

x = {{{(-2)/(-0.3)}}} = {{{20/3}}} = {{{6}}}{{{2/3}}} liters.


<U>Answer</U>.  {{{6}}}{{{2/3}}} liters of the 70% solution and  the rest  (20- {{{6}}}{{{2/3}}}) = {{{13}}}{{{1/3}}} liters of the 70% solution.
</pre>

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For introductory lessons covering various types of mixture word problems see

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/mixtures/Mixture-problems.lesson>Mixture problems</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/mixtures/More-Mixture-problems.lesson>More Mixture problems</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/mixtures/Solving-typical-mixture-problems.lesson>Solving typical word problems on mixtures for solutions</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/mixtures/Typical-word-problems-on-mixtures-from-the-archive.lesson>Typical word problems on mixtures from the archive</A>

in this site.


You will find there ALL TYPICAL mixture problems with different methods of solutions,
explained at different levels of detalization, &nbsp;from very detailed to very short.


Read them and become an expert in solution mixture word problems.


Also, &nbsp;you have this free of charge online textbook in ALGEBRA-I in this site

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-I - YOUR ONLINE TEXTBOOK</A>.


The referred lessons are the part of this textbook in the section "<U>Word problems</U>" under the topic "<U>Mixture problems</U>".



Save the link to this online textbook together with its description


Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson


to your archive and use it when it is needed.