Question

16. The sum of an infinitely descending geometric progression is 32
and the sum of the first five terms is 31. Find the common ratio
of the progression.
17
Find the​

Answer 1

If you have an infinite geometric series with first term aa and common ratio rr (with |r|<1|r|<1) then the sum ss is

s=a1−r

s=a1−r

In your problem, you know ss and aa --- can you solve for rr?

EDIT: OP has clarified that the number of terms is 33.

That means the terms are 33, 3r3r, and 3r23r2. And they add up to 3939.