Answer: [tex]184,724.153[/tex]
Step-by-step explanation:
Given
In 1990, there were 1200 cell phone subscriber in small town of stephenville
It is increasing by 75% per year after 1990
In year 1991 it is
[tex]\Rightarrow 1200+1200\times 0.75\\\Rightarrow 122(1.75)[/tex]
In year 1992 it is
[tex]\Rightarrow 1200(1.75)+1200(1.75)\times 0.75\\\Rightarrow 1200(1.75)(1+0.75)\\\Rightarrow 1200(1.75)^2[/tex]
So, it is increasing as [tex]1200(1.75)^x[/tex]
where [tex]x=[/tex]no of years spent
After 9 years, it is
[tex]\Rightarrow 1200(1.75)^9=184,724.153[/tex]