Question 1073227
Let n be the amount invested at 12%, and be the amount invested at 13%. Then the amount invested at 14% would be n+m. So:
n+m+(n+m)=3000
.12n+.13m+.14(n+m)=400
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2n+2m=3000
.26n+.27m=400
.26n+.26m=3000*.13=390
.01m=10
m=1000
n=500
m+n=1500
$500 was invested at 12%, $1000 was invested at 13%, and $1500 was invested at 14%. ☺☺☺☺