Given
initial investment of $3500
Rate = 4%
Find
a) Write an exponential function
b) Find the account balance after 18 years
Explanation
as we know the exponential function is in the form of
[tex]y=A(1+r)^t[/tex]
here , we have given , A = $3500 , r = 4%
so ,
[tex]\begin{gathered} y=3500(1+\frac{4}{100})^t \\ \\ y=3500(1.04)^t \\ \end{gathered}[/tex]
b) account balance after 18 years =
[tex]\begin{gathered} y=3500(1.04)^{18} \\ \\ y=3500\times(1.04\times1.04\times1.04\times1.04\times.......18\text{ times\rparen} \\ \\ y=3500\times2.02582(approx) \\ \\ y=7090.3578038 \end{gathered}[/tex]
Final Answer
therefore ,
a) Exponential function is
[tex]y=3500(1.04)^t[/tex]
b) amount balance = $7090.36
