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You invested $3,000\$3,000 in a savings account, and after 55 years, the balance grew to $4,665\$4,665. The interest is compounded annually. What is the annual interest rate?? \newlineUse the formula A=P(1+rn)ntA = P\left(1 + \frac{r}{n}\right)^{nt}, where AA is the balance (final amount), PP is the principal (starting amount), rr is the interest rate expressed as a decimal, nn is the number of times per year that the interest is compounded, and tt is the time in years. \newlineRound your answer to the nearest tenth.

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Q. You invested $3,000\$3,000 in a savings account, and after 55 years, the balance grew to $4,665\$4,665. The interest is compounded annually. What is the annual interest rate?? \newlineUse the formula A=P(1+rn)ntA = P\left(1 + \frac{r}{n}\right)^{nt}, where AA is the balance (final amount), PP is the principal (starting amount), rr is the interest rate expressed as a decimal, nn is the number of times per year that the interest is compounded, and tt is the time in years. \newlineRound your answer to the nearest tenth.
  1. Identify values: Identify the values of AA, PP, nn, and tt.
    A = $4,665\$4,665
    P = $3,000\$3,000
    n = 11 (compounded annually)
    t = 55 years
  2. Use formula: Use the formula A=P(1+rn)ntA = P\left(1 + \frac{r}{n}\right)^{nt} and substitute the values.\newline 4665=3000(1+r1)154665 = 3000\left(1 + \frac{r}{1}\right)^{1 \cdot 5}\newline 4665=3000(1+r)54665 = 3000(1 + r)^5
  3. Isolate (1+r)5(1 + r)^5:\newline Divide both sides by 3,0003,000 to isolate (1+r)5(1 + r)^5.\newline 4,6653,000=(1+r)5\frac{4,665}{3,000} = (1 + r)^5\newline 1.555=(1+r)51.555 = (1 + r)^5
  4. Take fifth root: Take the fifth root of both sides to solve for (1+r) (1 + r) . \newline(1.555)15=1+r (1.555)^{\frac{1}{5}} = 1 + r 1.092=1+r 1.092 = 1 + r
  5. Solve for rr: Subtract 11 from both sides to solve for rr.\newline 1.0921=r1.092 - 1 = r\newline r=0.092r = 0.092
  6. Convert to percentage: Convert rr to a percentage by multiplying by 100100.\newline 0.092×100=9.2%0.092\times 100 = 9.2\%The annual interest rate, rounded to the nearest tenth, is approximately 9.2%9.2\%.

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