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2 years ago

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A stockbroker has money in three accounts. The interest rates on the three accounts are 7%, 8%, 9%. If she has twice as much mon

ey invested at 8% as she does in 7% Three times as much at 9%
as she has at 7%, and the total interest for the year is $150 how much is invested at each rate?

The stockbroker invested $___at 7%,$___at 8%, and $___at 9%

1 answer:

Sveta_85 [38]2 years ago

5 0

Answer:

x=amount invested at 7%

2x=amount invested at 8%

3x=amount invested at 9%

interest=principal*rate*time (time=1 year)

$150=0.07x+0.08*2x+0.09*3x

$150=0.07x+0.16x+0.27x

$150=0.50x

$1500=5x

x=$300 invested at 7%

2x=$600 invested at 8%

3x=$900 invested at 9%

Step-by-step explanation:

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