<PRE><B>Question 1129724</B>
h, amount of the 55% acid to use
465-h, amount of the 25% acid to use

{{{55h+25(465-h)=45*465}}}
-
{{{55h-25h+25*465=45*465}}}

{{{30h+25*465=45*465}}}

{{{30h=(45-25)465}}}

{{{30h=20*465}}}

{{{h=(2/3)465}}}

{{{highlight(h=310)}}}--------liters of the 55% HCl




----------------MIS-HANDLED METHOD--------------------

From 25% up to 55%
Want 45% result

25, 30, 35, 40, 45, 50, 55--------
{{{(45-25)/(55-25)}}}

{{{2/3}}}

45 %  is  {{{2/3}}} of the way from 25% to 55%.


Liters of the 25% HCl?
{{{cross(465(2/3))}}}


{{{cross(310*Liters)}}}-----of the 25% HCl</PRE>