Question

What is the next term in the geometric sequence -270, 90, -30?

Answer 1

$b_1=-270, b_2=90, b_3=-30, b_4=?$

Common ratio: $q= \frac {b_2} {b_1} = \frac {90}{-270} = -\frac{1}{3},$ then

$b_4=b_3 \cdot q=-30 \cdot (-\frac {1}{3})= 10$

Answer: $b_4=10$