Find the common ratio.

Answer:
324, -972, 2916
Step-by-step explanation:
Divide a number by the previous number to find r.
r = -12/4 = -3
Multiply a number by r to find the next number.
-108 * (-3) = 324
324 * (-3) = -972
-972 * (-3) = 2916
Answer: 324, -972, 2916