I'm sure is true hopefully.
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Sum of geometric sequence
for the sum where the initial value is a₁ and the common ratio is r and the term is n

common ratio is -3
-5 times -3 is 15, -15 times -3=-45 etc
first term is -5
and we want the 8th term





the sum is 8200
The ratio is 91/120 because 91 is only divisible by 1, 7, 13, 91 and 120 is not divisible by 7, 13, or 91 so you cannot reduce this ratio
The answer is the middle one.