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Juelle had $25,000 to invest. She invested part of that amount at 3% interest and part at 5% interest for one year. The amount of interest she earned for both investments was $1100. How much was invested at each rate?

User Karola
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1 Answer

9 votes

Answer:

The first amount invested at 3%= x = $7500

The second amount Invested at 5% = y = $17500

Explanation:

Juelle had $25,000 to invest.

She invested part of that amount at 3% interest and part at 5% interest for one year.

The amount of interest she earned for both investments was $1100.

The formula for Simple Interest =

Principal × Rate × Time

Let us represent

The first amount invested at 3%= x

The second amount Invested at 5% = y

x + y= $25,000....... Equation 1

x = 25,000 - y

3% × x + 5% × y = $1100...... Equation 2

0.03x + 0.05y = 1100...... Equation 2

We substitute 25000 - y for x in Equation 2

0.03x + 0.05y = 1100

0.03(25000 - y) + 0.05y = 1100

750 - 0.03y + 0.05y = 1100

Collect like terms

- 0.03y + 0.05y = 1100 - 750

0.02y = 350

y = 350/0.02

y = 17500

Solving for x

x = 25,000 - y

x = 25000 - 17500

x = 7500

Therefore:

The first amount invested at 3%= x = $7500

The second amount Invested at 5% = y = $17500

User Jimit Shah
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