Math Problem Statement

Suppose that you want to have a $32,000 retirement fund after 38 years. How much will you need to deposit now if you can obtain an APR of 9.3%, compounded daily? Assume that no additional deposits are to be made to the account.

Solution

To determine how much you need to deposit now to have a $32,000 retirement fund after 38 years with an APR of 9.3% compounded daily, we use the formula for compound interest:

A=P(1+rn)ntA = P \left(1 + \frac{r}{n}\right)^{nt}

Where:

  • AA is the amount you want in the future (in this case, $32,000),
  • PP is the present value (the amount to deposit now),
  • rr is the annual interest rate (9.3% or 0.093),
  • nn is the number of times the interest is compounded per year (365 times, for daily compounding),
  • tt is the time in years (38 years).

We need to solve for PP, which can be rearranged from the formula:

P=A(1+rn)ntP = \frac{A}{\left(1 + \frac{r}{n}\right)^{nt}}

Now, substituting the values:

P=32000(1+0.093365)365×38P = \frac{32000}{\left(1 + \frac{0.093}{365}\right)^{365 \times 38}}

Let me calculate that for you.You would need to deposit approximately $934.43 now in order to have a $32,000 retirement fund after 38 years, with an APR of 9.3% compounded daily.

Would you like more details or have any questions about this calculation?

Here are 5 related questions you might consider:

  1. What happens if the interest rate changes to 8% APR?
  2. How much more would you need to deposit if the compounding was quarterly instead of daily?
  3. How would the final amount change if you extended the investment period to 40 years?
  4. What would happen if you made additional deposits during the investment period?
  5. How does daily compounding compare to monthly or yearly compounding?

Tip: The more frequently the interest is compounded, the greater the effect of interest on your final amount!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Compound Interest
Time Value of Money
Exponential Growth

Formulas

Compound Interest Formula: A = P (1 + r/n)^(nt)
Present Value Formula: P = A / (1 + r/n)^(nt)

Theorems

Exponential Growth Theorem

Suitable Grade Level

Grades 10-12