Question 355242
Let A be the amount of 20% solution, B the amount of 10% solution.
Total volume:
1.{{{A+B=50}}}
.
.
Total concentration:
{{{20A+10B=12(50)}}}
2.{{{2A+B=60}}}
.
.
Subtract eq. 1 from eq. 2,
{{{2A+B-A-B=60-50}}}
{{{highlight(A=10)}}}liters
Then from eq. 1,
{{{10+B=50}}}
{{{highlight(B=40)}}}liters