.
The "solution" by @josgarithmetic, giving the unique value of to the common ratio, is UNCOMPLETED,
and, therefore, INCORRECT.
I came to bring the correct solution.
= 24
=
= r^2 = = = , where r is the common ratio of the progression.
Therefore, the common ratio r may have TWO possible values, r = and r = .
Therefore, looking for , we should consider TWO cases.
Case 1. r = . Then = = = .
Case 2. r = - . Then = = = - .
ANSWER. Under given conditions, the 10-th term, , may have one of the two values
= or = - .
Solved.