Question 976866


recall: The fixed amount multiplied is called the common ratio, {{{r}}}, referring to the fact that the ratio (fraction) of the second term to the first term yields this common multiple.  
To find the common ratio, {{{divide}}} the second term by the first term.

in your sequence {{{4}}}, {{{16}}}, {{{64}}}, {{{256}}}, {{{1024}}},the second term is {{{16}}} and the first term is {{{4}}}, so divide {{{16}}} by {{{4}}}

{{{r=16/4=4}}} and the common ratio is {{{4}}} and your answer is 

d. {{{4}}} 

in {{{3}}}, {{{-9}}}, {{{27}}}, {{{-81}}}, {{{243}}} will be

{{{r=-9/3=-3}}}

and your answer is 

b.  {{{-3}}}