Question 368550
Let A be the number of ounces of 5% alchol solution, B the ounces of a 15% alchol solution.
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Total volume:
1.{{{A+B=40}}}
Total concentration:
{{{5A+15B=9(40)}}}
2.{{{A+3B=72}}}
Subtract eq. 1 from eq. 2,
{{{A+3B-A-B=72-40}}}
{{{2B=32}}}
{{{highlight(B=16)}}}ounces
From eq. 1,
{{{A+16=40}}}
{{{highlight(A=24)}}}ounces