SOLUTION: Roberto invested some money at 7%, and then invested $2000 more than twice this amount at 11%. His total annual income from the two investments was $3990. How much was invested at
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Question 154884: Roberto invested some money at 7%, and then invested $2000 more than twice this amount at 11%. His total annual income from the two investments was $3990. How much was invested at 11%? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Roberto invested some money at 7%, and then invested $2000 more than twice this amount at 11%. His total annual income from the two investments was $3990. How much was invested at 11%?
:
Let x = amt invested at 7%
:
It said,"invested $2000 more than twice this amount at 11%." therefore
(2x+2000) = amt invested at 11%
:
Write an income equation:
7% income + 11% income = $3990
:
.07x + .11(2x+2000) = 3990
:
.07x + .22x + 220 = 3990
:
.29x = 3990 - 220
:
.29x = 3770
x =
x = $13000 invested at 7%
:
Find amt invested at 11%
2(13000) + 2000 =
26000 + 2000 = $28000 invested at 11%
:
:
Check solution
.07(13000) + .11(28000) =
910 + 3080 = 3990; confirms our solution
