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You invested $7,500\$7,500 in a savings account, and after 88 years, the balance grew to $12,282.50\$12,282.50. The interest is compounded annually. What is the annual interest rate? Use 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. Round your answer to the nearest tenth.

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Q. You invested $7,500\$7,500 in a savings account, and after 88 years, the balance grew to $12,282.50\$12,282.50. The interest is compounded annually. What is the annual interest rate? Use 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. Round your answer to the nearest tenth.
  1. Given Values: We have: A = $12,282.50\$12,282.50, P = $7,500\$7,500, t = 88 \text{ years}, n = 11 \text{ (compounded annually)}. Formula: A = P\left(11 + \frac{r}{n}\right)^{nt}
  2. Substitute into Formula: Substitute the values into the formula: 12,282.50=7,500(1+r1)1812,282.50 = 7,500(1 + \frac{r}{1})^{1 \cdot 8}
  3. Simplify Equation: Simplify the equation: 12,282.50=7,500(1+r)812,282.50 = 7,500(1 + r)^8
  4. Divide by 7,5007,500: Divide both sides by 7,5007,500: (12,282.50/7,500)=(1+r)8(12,282.50 / 7,500) = (1 + r)^8 1.6376667=(1+r)81.6376667 = (1 + r)^8
  5. Take 88th Root: Take the 88th root of both sides to solve for (1+r) (1 + r) : (1.6376667)(1/8)=1+r (1.6376667)^{(1/8)} = 1 + r 1.063=1+r 1.063 = 1 + r
  6. Solve for (1+r)(1 + r): Subtract 11 from both sides to solve for rr: 1.0631=r1.063 - 1 = r r=0.063r = 0.063
  7. Convert to Percentage: Convert rr to a percentage: r=0.063imes100r = 0.063 imes 100 r=6.3extextpercentr = 6.3 ext{ extpercent}

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