To calculate the amount of interest earned in the second year of a compound interest investment, you can start with the information provided.
You initially have an investment of $1,000 at an annual interest rate of 8%.
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Calculate the amount at the end of the first year:
\[ A_1 = P(1 + r) \] where:
- \( P = 1000 \) (initial investment),
- \( r = 0.08 \) (annual interest rate).
\[ A_1 = 1000(1 + 0.08) = 1000 \times 1.08 = 1080 \]
So, the amount after the first year is $1,080. The interest earned in the first year is:
\[ \text{Interest}_1 = A_1 - P = 1080 - 1000 = 80 \]
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Calculate the amount at the end of the second year:
Now, we use the amount at the end of the first year as the principal for the second year:
\[ A_2 = A_1(1 + r) = 1080(1 + 0.08) \]
\[ A_2 = 1080 \times 1.08 = 1166.40 \]
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Calculate the interest earned in the second year:
To find the interest earned in the second year, subtract the amount at the end of the first year from the amount at the end of the second year:
\[ \text{Interest}_2 = A_2 - A_1 = 1166.40 - 1080 = 86.40 \]
So, the interest earned in the second year is $86.40.