Question 1202656
<pre>
     CONC.%         VOLUME         PURE SALT
        9             d              0.09d
        17           70              0.17*70
        13           d+70           0.09d+0.17*70
</pre>
{{{0.09d+(0.17)(70)=0.13(d+70)}}}
Simplify and solve for d.


{{{0.09d+0.17*70=0.13d+0.13*70}}}

{{{0.17*70-0.13*70=0.13d-0.09d}}}

{{{(0.13-0.09)d=70(0.17-0.13)}}}

{{{d=70((0.17-0.13)/(0.13-0.09))}}}

{{{d=70(0.04/0.04)}}}

{{{d=70*1}}}

{{{highlight(d=70)}}}  ------------notice, the same amount of 9% as the 17%