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Find the interest rate for a $3000 deposit accumulating to $3632, compounded annually for 7 years. The interest rate is ___ %. (Do not round until the final answer. Then round to two decimal places as needed.)

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Final answer:

To find the interest rate, we can use the formula for compound interest. Plugging in the given values and solving for r, we find that the interest rate is approximately 4.47%.

Step-by-step explanation:

To find the interest rate, we can use the formula for compound interest:

A = P(1 + r/n)^(nt)

Where:

  • A = final amount
  • P = principal amount
  • r = annual interest rate (as a decimal)
  • n = number of compounding periods per year
  • t = number of years

In this case, we have:

  • A = $3632
  • P = $3000
  • n = 1 (compounded annually)
  • t = 7 years

Plugging in these values, we can solve for r:

$3632 = $3000(1 + r/1)^(1*7)

Dividing both sides by $3000 and taking the logarithm, we get:

log(3632/3000) = 7log(1 + r/1)

Simplifying, we find:

log(3632/3000) / 7 = log(1 + r)

Using a calculator to evaluate the logarithms, we find:

0.0449 = log(1 + r)

Converting back to exponential form, we get:

1 + r = 10^(0.0449)

Subtracting 1 and multiplying by 100, we find:

r = (10^(0.0449) - 1) * 100

Rounding to two decimal places, the interest rate is approximately 4.47%.

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