Question 1012076
 A financial planner invested a certain sum at 9%,
let x = amt invested at 9%
 twice that amount at 10%,
(2x) = amt invested at 10%
 and three times that amount at 11%.
(3x) = amt invested at 11%

find the amount invested at each rate if her total yearly income from the three investments was P27900. 
:
.09x + .1(2x) + .11(3x) = 27900
.09x + .2x + .33x = 27900
.62x = 27900
x = 27900/.62
x = 45000 invested at 9%
I'll let you find the amts invested at 10 and 11%