Question 336519
Let A be the amount invested at 7%, B the amount invested in 9%.
1.{{{A+B=3700}}}
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{{{(7/100)A+(9/100)B=297}}}
2.{{{7A+9B=29700}}}
From eq. 1,
{{{A=3700-B}}}
Substitute into eq. 2,
{{{7(3700-B)+9B=29700}}}
{{{25900-7B+9B=29700}}}
{{{2B=3800}}}
{{{highlight(B=1900)}}}
Then from eq. 1,
{{{A+1900=3700}}}
{{{highlight(A=1800)}}}
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$1800 invested at 7% and $1900 invested at 9%.