Answer: Common ratio is 
Step-by-step explanation: Given sequence −15,−9,−275,−8125,...
The general terms of a geometric sequence are:
.
In common ratio is given by dividing next term from previous term

Therefore, <em>in order to find the common ratio for the given geometric sequence, we need to divide second term by first term or third term by second term.</em>
Dividing second term by first term, we get

Dividing top and bottom by -3, we get
.
<h3>Therefore, common ratio is

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