SOLUTION: how do i turn this word problem into a linear system of equations? and as a matrix equation? the problem: you have 20,000 to invest inn three types of stocks. you expect the annu

Algebra ->  Matrices-and-determiminant -> SOLUTION: how do i turn this word problem into a linear system of equations? and as a matrix equation? the problem: you have 20,000 to invest inn three types of stocks. you expect the annu      Log On


   

Question 387103: how do i turn this word problem into a linear system of equations? and as a matrix equation?
the problem: you have 20,000 to invest inn three types of stocks. you expect the annual returns on stock x, stock y, and stock z to be 12%, 10% and 6% as respectively. you want to combine investment in stock y and z to be 3x the amount invested in stock x. you want your overall annual return to be 9%
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how do i turn this word problem into a linear system of equations? and as a matrix equation?
the problem: you have 20,000 to invest in three types of stocks. you expect the annual returns on stock x, stock y, and stock z to be 12%, 10% and 6% as respectively. you want to combine investment in stock y and z to be 3x the amount invested in stock x. you want your overall annual return to be 9%
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Equations:
x + y + z = 20,000
-3x+ y + z = 0
0.12x + 0.10y + 0.06z = 0.09(20,000)
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Using a matrix method to solve you get:
x = 5000
y = 7500
z = 7500
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Cheers,
Stan H.
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