Question

Which sets of numbers represent geometric sequences? Check all that apply.

Answer 1

Answer:

Geometric sequences are below in bold.

Step-by-step explanation:

First one is 2/5, 2/10, 2/20, 2/40

2/10 = 2/5 * 1/2 ; 2/20 = 2/10 * 1/2

This is geometric with common ratio 1/2.

Second is  11/12, 8/12, 5/12, 2/12

This is not geometric It is arithmetic with common difference  -3/12.

25, 19, 13, 7....     is arithmetic with d = -6

4, 12, 36, 108

12 = 3*4, 36 = 3*12   and so on

This is geometric with r = 3.

-5, 5, -5, 5,...

Each term is obtained from the prievious by multiplying by - 1. S

this is geometric with r = -1.

-3, 0, 3, 6 is arithmetic with d = 3.

-8, -2, 1/2, 1/8

This is not geometric as there is no common ratio.