Math Problem Statement

At age 24​, someone sets up an IRA​ (individual retirement​ account) with an APR of 8​%. At the end of each month he deposits ​$45 in the account. How much will the IRA contain when he retires at age​ 65? Compare that amount to the total deposits made over the time period. Question content area bottom Part 1 After retirement the IRA will contain ​$    enter your response here. ​(Do not round until the final answer. Then round to the nearest cent as​ needed.)

Solution

To calculate how much the IRA will contain at retirement, we need to use the future value formula for a series of monthly contributions, which is given by the formula for the future value of an annuity due:

FV=P×((1+r)n1r)FV = P \times \left( \frac{{(1 + r)^n - 1}}{r} \right)

Where:

  • FVFV is the future value of the IRA at retirement
  • PP is the monthly deposit ($45)
  • rr is the monthly interest rate (APR divided by 12) = 8% annual interest rate → r=8%12=0.0812=0.006667r = \frac{8\%}{12} = \frac{0.08}{12} = 0.006667
  • nn is the number of monthly deposits (since the person starts at 24 and retires at 65, the number of months is n=(6524)×12=41×12=492n = (65 - 24) \times 12 = 41 \times 12 = 492)

Now, let's plug in the values into the formula:

FV=45×((1+0.006667)49210.006667)FV = 45 \times \left( \frac{{(1 + 0.006667)^{492} - 1}}{0.006667} \right)

We can calculate the future value step by step.

Let’s calculate this value:

FV=45×((1.006667)49210.006667)FV = 45 \times \left( \frac{{(1.006667)^{492} - 1}}{0.006667} \right)

First, calculate (1.006667)492(1.006667)^{492}, then subtract 1, divide by 0.006667, and multiply by 45.

Let me compute that for you. Given values P = 45 # monthly deposit in dollars r = 0.006667 # monthly interest rate n = 492 # number of months (41 years * 12 months)

Calculating the future value of the IRA

FV = P * (((1 + r) ** n - 1) / r) FVThe IRA will contain approximately $170,714.81 when the person retires at age 65.

Total Deposits:

To calculate the total deposits made over the period, we simply multiply the monthly deposit by the number of months:

Total Deposits=P×n=45×492=22,140\text{Total Deposits} = P \times n = 45 \times 492 = 22,140

So, the total deposits over the 41 years will be $22,140.

Comparison:

  • Total Deposits: $22,140
  • Future Value at Retirement: $170,714.81

The difference, or the growth due to interest, is approximately $148,574.81.

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

Here are a few questions that could expand your understanding:

  1. How does compounding interest affect the growth of savings over time?
  2. What would the future value be if the interest rate were increased to 10%?
  3. How can adjusting the monthly deposit amount affect the final value?
  4. What are the key factors in choosing the right retirement account?
  5. How does the time horizon impact the total amount saved for retirement?

Tip: Starting to save early and regularly, even with small amounts, can have a huge impact on your retirement savings due to the power of compound interest.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Compound Interest
Future Value of Annuities
Annuity Calculations
Interest Rates

Formulas

Future Value of an Annuity Formula: FV = P × ((1 + r)^n - 1) / r

Theorems

Compound Interest Theorem
Annuity Theorem

Suitable Grade Level

Grades 9-12