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Mia has an investment that is worth $12,000 after 4 years. If the initial investment was $8,000, what is the annual simple interest rate?

User Slavatron
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1 Answer

3 votes

Answer: 12.5 %

Step-by-step explanation:

Hi, to answer this question we have to apply the simple interest formula:

I = p x r x t

Where:

I = interest (investment after interests - principal; 12000-8000=4000)

P = Principal Amount (initial invest)

r = Interest Rate (decimal form)

t= time

Replacing with the values given

4,000= 8,000 (x) 4

Solving for x :

4,000= 32,000x

4,000/ 32,000 =x

x= 0.125

Since the interest rate is in decimal form, we have to multiply it by 100 to obtain the percentage.

0.125 x 100 = 12.5 %

Feel free to ask for more if needed or if you did not understand something.

User StefanJM
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