Answer:
r = [tex]\frac{1}{3}[/tex]
Step-by-step explanation:
Calculate the ratio between consecutive terms, that is
[tex]\frac{18}{54}[/tex] = [tex]\frac{1}{3}[/tex]
[tex]\frac{6}{18}[/tex] = [tex]\frac{1}{3}[/tex]
[tex]\frac{2}{6}[/tex] = [tex]\frac{1}{3}[/tex]
Thus the common ratio r = [tex]\frac{1}{3}[/tex]
