Question 1204463
If use v liters of the pure 100% acid, then use 45-v liters of the 10% acid.


To account for the amount of pure acid for the mixture,
{{{v+0.10(45-v)=0.40*45}}}
-
{{{v+(0.1)(45)-0.1v=(0.4)(45)}}}

{{{(1-0.1)v=0.4*45-0.1*45}}}

{{{v=45((0.4-0.1)/(1-0.1))}}}----------think about this expression a bit, before continuing...



{{{v=45(1/3)}}}


{{{highlight(v=15)}}}------and you know the quantity for the 10% acid is 30 L.
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