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You have $100 available today to invest for twenty years and the annual interest rate is 8 percent. The interest payments are to be reinvested, also at a rate of 8 percent. How much will you have available twenty years from now?

User Brendenw
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Final answer:

After 20 years of reinvesting $100 at an annual interest rate of 8 percent, you will have approximately $466.10 due to the power of compound interest.

Step-by-step explanation:

If you have $100 to invest at an annual interest rate of 8 percent, and you reinvest the interest payments also at 8 percent for 20 years, you're dealing with a case of compound interest. The general formula for compound interest is A = P(1 + r/n)nt, where:

  • P is the principal amount (the initial amount of money)
  • r is the annual interest rate (decimal)
  • n is the number of times that interest is compounded per year
  • t is the time the money is invested or borrowed for, in years
  • A is the amount of money accumulated after n years, including interest.

Since the interest is compounded annually, n is 1. Therefore, the formula simplifies to A = P(1 + r)t.

For your specific question, you will use the following values:

  • P = $100
  • r = 0.08 (8% expressed as a decimal)
  • n = 1 (since interest is compounded annually)
  • t = 20 years

The calculation will be A = 100(1 + 0.08)20.

Now performing the calculation:

A = 100(1.08)20
A ≈ 100(4.66)
A ≈ $466.10

Therefore, after 20 years, you will have approximately $466.10 available.

User Likethesky
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