Question 1095075
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Erica invests some money in three different accounts. she put some of it in a CD earning 3% and twice as much in an IRA 
paying 4% simple interest. she also decided to invest $1000 more than what she has invested in the cd Into a money mutual fund 
earning 5% simple interest. Determine how much money Erica invested in each account if she earned $370 in interest after 1 year.
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Let "x" be the amount (in dollars) Erica invested in CD earning 3%.

Then the amount invested in the IRA paying 4% is 2x, according to the condition.


Similarly, her investment in the mutual fund  is (x+1000) dollars.


Now you are ready to write the "earnings equation":

0.03*x + 0.04*(2x) + 0.05*(x+1000) = 370.


Simplify:

0.03x + 0.08x + 0.05x + 50 = 370  ====>

0.16x = 370 - 50 = 320  ====>  x = {{{320/0.16}}} = 2000.


So, Erica invested  $2000 at 3%,  $4000 at 4%  and  $3000 at 5%.


<U>Check</U>.  0.03*2000 + 0.04*4000 + 0.05*3000 = 370 dollars.  ! Correct !
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Solved.