207k views
3 votes
Anna wants to have $100,000 saved up by the time she is 65. If Anna is currently 20 years old, how much money will she have to invest at 7%, compounded annually, in order to accomplish this goal?

User Charbel
by
6.8k points

1 Answer

3 votes

Final answer:

Anna will need to invest approximately $19,533.29

Step-by-step explanation:

To calculate the amount of money Anna will need to invest, we can use the formula for compound interest:

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

Where:

  • A is the future value of the investment
  • P is the principal amount (initial investment)
  • r is the annual interest rate (as a decimal)
  • n is the number of times the interest is compounded per year
  • t is the number of years

In this case, Anna wants to have $100,000 in the future, so A = $100,000. The principal amount is what we are trying to find, so we will call it P. The interest rate is 7%, so r = 0.07. The interest is compounded annually, so n = 1. Anna is currently 20 years old, and she wants to have the money by the time she is 65, so t = 65 - 20 = 45 years.

Now we can substitute these values into the formula:

$100,000 = P(1 + 0.07/1)^(1*45)

Simplifying:

$100,000 = P(1.07)^45

Dividing both sides of the equation by (1.07)^45, we get:

P = $100,000 / (1.07)^45

Calculating this on a calculator or computer, we find:

P ≈ $19,533.29

User Entity Black
by
7.8k points