SOLUTION: Donna invested her $33,000 bonus and received a total of $970 in interest after 1 year. If part of her money returned 4% and the remainder 2.25% then how much did she invest at ea

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Question 146114: Donna invested her $33,000 bonus and received a total of $970 in interest after 1 year. If part of her money returned 4% and the remainder 2.25% then how much did she invest at each rate?
Found 2 solutions by ankor@dixie-net.com, josmiceli:
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
Donna invested her $33,000 bonus and received a total of $970 in interest after 1 year. If part of her money returned 4% and the remainder 2.25% then how much did she invest at each rate?
:
Let x = amt invested at 4%
:
The total invested was given as 33000, therefore:
(33000-x) = amt invested at 2.25%
:
Int at 4% + int at 2.25% = $970
.04x + .0225(33000-x) = 970
:
.04x + 742.5 - .0225x = 970
:
.04x - .0225x = 970 - 742.5
:
.0175x = 227.5
x =
x = $13,000 invested at 4%
and
33000 - 13000 = $20,000 invested at 2.25%
:
:
Check solutions
.04(13000) + .0225(20000) =
520 + 450 = 970; confirms our solutions

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
Let = amount invested @ 4%
Let = amount invested @ 2.25%

She invested $13,000 at 4% and $20,000 at 2.25%
check answer:

OK