Question

Determine if the sequence below is arithmetic or geometric and determine the common difference/ratio in simplest form 125,25,5

Answer 1

series: 125, 25, 5, ...

We can identify geometric series by:

√first term x third term = second term

√125 x 5 = 25

Hence this is a geometric series.

Common difference:

25 ÷ 5      or     125 ÷ 25

5                            5

The common difference is equal to 5.