Question 1158615
<pre>
                      %           vol         solute

STERILE WATER          0           x             0

SOLUTION              60          60            60*60

MIXTURE RESULT        40          x+60          40(x+60)
</pre>
{{{(60*60)/(x+60)=40}}}

-

{{{3600=40(x+60)}}}

{{{40x+2400=3600}}}

{{{40x=800}}}

{{{highlight(x=20)}}}-----ml. of the sterile water.