Question

What is the common ratio for the sequence 5,-10,20,-40?

Answer 1

-2

Explanation:

Answer 2

The COMMON RATIO of the sequence is -2.

Explanation:

Here, the given sequence is:

5, -10, 20 ,-40

Here, The first term ( a 1 ) of the sequence is (5)

The second term (a 2) of the sequence is (-10)

Third term of sequence (a 3) is 20

Now, calculating the common ratio (r) of sequence ,we get:

`(a_2)/(a_1) =  r  = ((-10)/(5)) = -2\\(a_3)/(a_2) =r  = ((20)/(-10)) = -2`

So, here r =(-2)

⇒ The COMMON RATIO of the sequence is -2.

Hence, the given sequence in in GEOMETRIC PROGRESSION.