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3 years ago

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A mother earned $8750.00 from royalties on her cookbook. She set aside 20% of this for a down payment on a new home. The balan

ce will be used for her son's future education. She invests a portion of the money in a bank certificate of deposit (CD account) that earns 4% and the remainder in a savings bond that earns 7%. If the total interest earned after one year is $420.00, how much money was invested at each rate?

1 answer:

Masteriza [31]3 years ago

5 0

The problem statement is not clear regarding which money is invested. We will assume it is the 80% of $8750 that is set aside for future education. That amount is

... 0.80 × $8750 = $7000

If x represents the amount invested at 7%, then the total interest earned is

... (7000 -x)×4% + (x)×7% = 420

... 280 +0.03x = 420

... x = 140/0.03 ≈ 4666.67

$4666.67 was invested at 7%.

$2333.33 was invested at 4%.

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