Suppose your​ friend's parents invest $ 20000 in an account paying 5 % compounded annually. What will the balance be after 5 ​years?

1 answer

To calculate the balance of an investment compounded annually, you can use the formula for compound interest:

\[ A = P(1 + r)^t \]

where:

  • \( A \) is the amount of money accumulated after n years, including interest.
  • \( P \) is the principal amount (the initial amount of money).
  • \( r \) is the annual interest rate (decimal).
  • \( t \) is the number of years the money is invested or borrowed.

Given:

  • \( P = 20000 \)
  • \( r = 0.05 \) (5% as a decimal)
  • \( t = 5 \)

Now plug in the values into the formula:

\[ A = 20000(1 + 0.05)^5 \]

Calculating inside the parentheses first:

\[ A = 20000(1.05)^5 \]

Now calculate \( (1.05)^5 \):

\[ (1.05)^5 \approx 1.2762815625 \]

Now multiply by the principal:

\[ A \approx 20000 \times 1.2762815625 \approx 25525.63 \]

Thus, the balance after 5 years will be approximately $25,525.63.