Algebra Investment Problems

ysodimu

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Oct 10, 2007
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I need help with this Algebra financial problems.

1. A charity deposited a total of $54,000 in two simple interest accounts. The annual simple interest rate on one account is 8%. The annual simple interest rate on the second account is 12%. How much was invested in each account if the total annual interest earned is 9% of the total investment?

2. Suki Hiroshi has made an investment of $2,500 at an annual simple interest rate of 7%. How much money does she have invested at an annual simple interest rate of 11% if the total interest earned is 9% of the total investment?

Thanks in advance for your help.
 

Subhotosh Khan

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ysodimu said:
I need help with this Algebra financial problems.

1. A charity deposited a total of $54,000 in two simple interest accounts. The annual simple interest rate on one account is 8%. The annual simple interest rate on the second account is 12%. How much was invested in each account if the total annual interest earned is 9% of the total investment?

2. Suki Hiroshi has made an investment of $2,500 at an annual simple interest rate of 7%. How much money does she have invested at an annual simple interest rate of 11% if the total interest earned is 9% of the total investment?

Thanks in advance for your help.
Please show us your work and exactly where you are stuck - so that we would know where to begin to help.
to start:
#1

Assume

the amount of dollars invested at 8% = E

the amount of dollars invested at 12% = T

Then

A charity deposited a total of $54,000 in two simple interest accounts

E + T = 54000.............................................................(1)

and

the total annual interest earned is 9% of the total investment


0.08*E + 0.12*T = 0.09 * 54000........................................(2)

Solve (1) and (2) for 'T' & 'E'

follow the same procedure for #2.
 

Loren

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Aug 28, 2007
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1,299
Sometimes it helps to get your thoughts organized by setting up a table. This can be done using one or two variables. I'll use one. The basic formula is "principal times rate times time equals amount of interest earned."

................principal X rate X time = interest

@8%............x.............08......1...........08x

@12%......54000-x.....12......1.........12(54000-x)

Total............54000......09.....1..........09(54000)

The next step is to find some things in the table from which we can build an equation. In other what things or combination of things are equal to each other. The words given in the problem furnish the clue.

.08x + .12(54000-x) = .09(54000)

You can probably take it from here.
 
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