Question 291713
Let T be the number of liters of 3% solution.
Let F be the number of liters of 5% solution. 
Then,
Volume equation:
1.{{{T+F=550}}}
Concentration equation:
{{{3T+5F=4.4(550)}}}
2.{{{3T+5F=2420}}}
From eq. 1,
{{{T+F=550}}}
{{{T=550-F}}}
Substitute into eq. 2 and solve for F.
{{{3T+5F=2420}}}
{{{3(550-F)+5F=2420}}}
{{{1650-3F+5F=2420}}}
{{{2F=770}}}
{{{F=385}}}
Then from eq. 1,
{{{T=550-385}}}
{{{T=165}}}
.
.
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165 liters of 3% solution and 385 liters of 5% solution.