Question 1207794
.
A laboratory has 60 cubic centimeters (cm^3) of a solution that is 40% HCl acid. 
(a) How many cubic centimeters of a 15% solution of HCl acid should be mixed with 
the 60 cm^3 of 40% acid to obtain a solution of 25% HCl? 
(b) How much of the 25% solution is there?
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            Your equation is incorrect.



<pre>
Let x be the volume of the 15% solution to add, in cubic centimeters.


The volume of the pure HCl in 60 cm^3 of the 40% HCl acid is 0.4*60 = 24 cm^3.


The volume of the final solution is (60+x) cm^3,

and the volume of the pure HCl acid in (60+x) cm^3 of the final 25% HCl acid is  0.25*(60+x) cm^3.



We make the setup equation by equating the volumes of pure HCl acid in 
ingredients and in final mixture


    0.4*60 + 0.15*x = 0.25*(60+x).


It is a proper setup equation.


You can take it and continue your solution from this point to find x.
</pre>

At this point, I completed my explanation on how to make a proper setup equation for this problem.


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It is a standard and typical mixture word problem for two ingredients. 


There is entire bunch of introductory lessons covering various types of mixture problems for two ingredients

&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/Word-problems-on-mixtures-for-antifreeze-solutions.lesson>Word problems on mixtures for antifreeze solutions</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/mixtures/Solving-typical-word-problems-on-mixtures-for-dry-substances-coffee-nuts.lesson>Word problems on mixtures for dry substances like coffee beans, nuts, cashew and peanuts</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/mixtures/Word-problems-on-mixtures-for-dry-substances-like-cookies-candies.lesson>Word problems on mixtures for dry substances like candies, dried fruits</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/mixtures/Word-problems-on-mixtures-for-dry-substances-like-soil-and-sand.lesson>Word problems on mixtures for dry substances like soil and sand</A>

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/mixtures/Word-problems-on-mixtures-for-alloys.lesson>Word problems on mixtures for alloys</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.