Answer :
The recursive geometric sequence that models this situation is:
[tex]f(n) = 0.9f(n-1)[/tex]
[tex]f(1) = 90000[/tex]
What is a geometric sequence?
A geometric sequence is a sequence in which the result of the division of consecutive terms is always the same, called common ratio q.
It can be represented by a recursive sequence as follows:
[tex]f(n) = qf(n-1)[/tex]
With f(1) as the first term.
In this problem, the sequence is: 90.000: 81,000; 72,900; 65,610, hence:
[tex]q = \frac{65610}{72900} = \cdots = \frac{81000}{90000} = 0.9[/tex]
[tex]f(1) = 90000[/tex]
Hence:
[tex]f(n) = 0.9f(n-1)[/tex]
[tex]f(1) = 90000[/tex]
More can be learned about geometric sequences at https://brainly.com/question/11847927