<PRE><B>Question 824100</B>
.4x+.12(30000-x)=2400
.04x+.12(30000)-.12x=2400
.04x+3600-.12x=2400
.12x-.04x+3600=2400 
.08x+3600=2400
.08x+3600-3600=2400-3600
8x=1200
(8x/8)=1200/8
X=1500
15000-30000=15000
Total invested at .12=$15,000.00
                           At .04=$15,000.00
15000*.04=$600.00
15000*.12=$1,800.00
$1,800.00+$600.00=$2,400.00
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