Recall that the equation for exponential growth can be written as
![\begin{gathered} y=I(1+r)^t \\ \text{where} \\ I\text{ is the initial value} \\ r\text{ is the rate of growth} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/okultv0ezh7xvw0vbgq1fbd8eladu3agui.png)
Given that the initial value of the chocolate bar is $0.48, and the rate increases by 2% annually. Then we have the following variables
I = 0.48
r = 0.02 (from 2%)
Then the equation to model the price of the chocolate bar is
![C(t)=0.48(1+0.02)^t](https://img.qammunity.org/2023/formulas/mathematics/college/awwd9e4uhum2iw0z0ccxr9hovocd2mesbv.png)