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Your checking account has a balance of $500. You can invest in an account that will

earn 4.8% annual interest compounded monthly for 5 years.

Use the formula
y = P(1+)nt

a. Write a function y that represents the total balance after tyears.
y(t)=______

b. Find the balance after 8 years.
About $:_______

User Afftee
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1 Answer

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Final answer:

The function y(t) represents the total balance after t years in the form y(t) = 500(1 + 0.048/12)^12t. After 8 years, using the formula and the given annual interest rate compounding monthly, the balance would be approximately $740.12.

Step-by-step explanation:

To answer the first part of the question, we need to write a function y(t) that represents the total balance after t years with an annual interest rate of 4.8% compounded monthly. The formula provided seems to have a typo as it lacks the rate in the parentheses. The correct formula for compound interest would be:

y = P(1 + r/n)nt

Where:

  • P is the principal amount (initial investment).
  • r is the annual interest rate (decimal).
  • n is the number of times interest is compounded per year.
  • t is the number of years the money is invested for.

To express this with the given data:

y(t) = 500(1 + 0.048/12)12

For the second part, to find the balance after 8 years, we substitute t with 8

y(8) = 500(1 + 0.048/12)12*8

Now, calculate the balance:

y(8) = 500(1 + 0.004)96

y(8) ≈ 500(1.004)96

y(8) ≈ 500 * 1.48024275

y(8) ≈ $740.12

Therefore, the balance after 8 years would be approximately $740.12.

User Larsks
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