Question 928007
One solution containing 20% alcohol is mixed with another solution containing 60% alcohol to make 20 gal of a solution that is 30% alcohol. How much of each solution is used?
<pre>
{{{(matrix(12,1,The,number, of, gallons, of, the, WEAKER, "solution,",which,is,x,gallons))}}}{{{""+""}}}{{{(matrix(12,1,The,number, of, gallons, of, the, STRONGER, "solution,",which,is,y,gallons))}}}{{{""=""}}}{{{(matrix(12,1,The,number, of, gallons, of, the, MEDIUM-STRENGTH, "solution,",which,is,20,gallons))}}}

So that's <font size=6>x+y = 20</font>

{{{(matrix(20,1,The,number, of, gallons, of, PURE,ALCOHOL,CONTAINED,IN,the,x,gallons,of,the, WEAKER, "solution,",which,is,(0.20)x,gallons))}}}{{{""+""}}}{{{(matrix(20,1,The,number, of, gallons, of, PURE,ALCOHOL,CONTAINED,IN,the,x,gallons,of,the, STRONGER, "solution,",which,is,(0.60)x,gallons))}}}{{{""=""}}}{{{(matrix(20,1,The,number, of, gallons, of, PURE,ALCOHOL,CONTAINED,IN,the,20,gallons,of,the, MEDIUN-STRENGTH, "solution,",which,is,(0.30)(20),gallons))}}}

So that's <font size=6>(0.20)x+(0.60)y = (0.30)(20)</font>

Solve the resulting system of two equations in two unknowns.

Answer:  x=15, y=5

Edwin</pre>