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George invested some money at 5% interest. George also invested $56 more than 5 times that amount at 10%. How much is invested at each rate if George receives $1434.50 in interest after one year? (Round to two decimal places if necessary.)

User Daveeloo
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1 Answer

17 votes
17 votes

ANSWER

The amount invested at 5% interest is $2598.00

The amount invested at 10% interest is $13,046.00

Explanation:

Given parameters

• Let the amount invested at a 5% rate be x

,

• The total amount received = $1434.50

George invested $x at 5% interest

George also invested $56 more than 5 times that amount at 10%

This can be written mathematically as

56 + 5(x)

56 + 5x ----------- amount invested at 10% interest

The total amount received = amount invested at 5% * interest rate + amount invested at 10% * interest rate

Mathematically,

1434.50 = 0.05(x) + 0.10(56 + 5x)

The next thing is to open the parentheses

1434.50 = 0.05x + 0.1 * 56 + 0.1 * 5x

1434.50 = 0.05x + 5.6 + 0.5x

Collect the like terms

1434.50 = 0.05x + 0.5x + 5.6

1434.50 = 0.55x + 5.6

Substract 5.6 from both sides

1434.50 - 5.6 = 0.55x + 5.6 - 5.6

1428.9 = 0.55x

Divide both sides by 0.55

1428.9/0.55 = 0.55x/0.55

1428.9/0.55 = x

x = $2,598.00

Hence, the amount invested at 5% interest is $2598.00

The next thing is to find the amount invested at 10% can be calculated below

The amount invested at 10% interest is 56 + 5x

Where x = $2598.00

Amount invested at 10% interest = 56 + 5x

Amount invested at 10% interest = 56 + 5(2598.00)

Amount invested at 10% interest = 56 + 12990

Amount invested at 10% interest = $13,046.00

Hence, the amount invested at 10% interest is $13,046.00

User TheLibrarian
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