Write a function that represents the balance y (in dollars) of the investment account after t years.

Question

You deposit $90 in an investment account that earns 7.2% annual interest compounded quarterly.

Write a function that represents the balance y (in dollars) of the investment account after t years.

y=

 

Question 2

What is the balance of the account after 4 years?

$

Answer 1

1. y = 90·(1 + 0.072/4)^4t = 90·1.018^4t;
2. y = 90·1.018¹⁶ = $119.73