<PRE><B>Question 1009777</B>
.
S=amount invested at 7%; N=amount invested at 9%
.
S+N=$20000
S=$20000-N
.
0.07S+0.09N=$1550
0.07($20000-N)+0.09N=$1550
$1400-0.07N+0.09N=$1550
0.02N=$150
N=$7500
ANSWER 1: $7500 was invested at 9%.
.
S=$20000-N=$20000-$7500=$12500
ANSWER 2: $12500 was invested at 7%.
.
CHECK:
0.07S+0.09N=$1550
0.07($12500)+0.09($7500)=$1550
$875+$675=$1550
$1550=$1550
.
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