![f(x)=28*(1.12)^x](https://img.qammunity.org/2023/formulas/mathematics/college/y9so9kdlwwis76ueianogw3o3eicq2r0nf.png)
The percent change is 12%, meaning after each interval x the new value is 112% times the previous value. This can be expressed as (for x = 1)
![\text{new value=28}*(112)/(100)](https://img.qammunity.org/2023/formulas/mathematics/college/pq02db4aqr8nqoxg69r1cqf40gjaz8mijr.png)
when x = 2 the above value becomes the "previous value" and therefore, the new value will be
![\text{new value =(28}*(112)/(100))*(112)/(100)](https://img.qammunity.org/2023/formulas/mathematics/college/vk8ykzbpdy48hpc904t25epm21i9ytc455.png)
when the above becomes the previous value the new value then will be
![\text{new value =((28}*(112)/(100))*(112)/(100))*(112)/(100)](https://img.qammunity.org/2023/formulas/mathematics/college/10pv9igty2sy2jb30atk9y5kqy004k9zqb.png)
and so on until we have x number of 122/100 =1.12 terms. Then the new value for any x can be written as
![\text{new value for any x=28(}(112)/(100))^x](https://img.qammunity.org/2023/formulas/mathematics/college/w1w1zsgwxnvdn53b9urhg76qndpcsrp0pg.png)
or
![f(x)=28(1.12)^x](https://img.qammunity.org/2023/formulas/mathematics/college/31a9x0jtgf7sa82nf0ixdmt7x7lf5khdz8.png)