Answer:
r = [tex]\frac{1}{4}[/tex]
Step-by-step explanation:
The common ratio (r) of a geometric sequence is the ratio of any term divided by the previous term , then
r = [tex]\frac{a_{2} }{a_{1} }[/tex] = [tex]\frac{160}{640}[/tex] = [tex]\frac{1}{4}[/tex]
