Question

Find the common ratio of the sequence -172 -86 -43 -21.5

Answer 1

to find the common ratio, divide the second term by the first term.
-86/-172 = 1/2

so 1/2 is ur common ratio

Answer 2

common ratio between successive terms in the sequence is
`(1)/(2)`

Explanation:

Common ratio(r) defined as the ratio of a term to the previous term.

also common ratio term is constant.

Given the sequence:

-172 -86 -43 -21.5

⇒
`a_1 = -172`

`a_2 = -86`

`a_3 = -43`

`a_4 = -21.5`

Then by definition of common ratio:

`r = (a_2)/(a_1)=(a_3)/(a_2)=(a_4)/(a_3)`

Substitute the given values we have;

`r = (-86)/(-172) = (-43)/(-86)=(-21.5)/(-43)`

⇒
`r = (1)/(2)`

Therefore, the common ratio between successive terms in the sequence is
`(1)/(2)`