Question

Determine if the following sequences are arithmetic or geometric and give the common difference or common ratio
100, 80, 64

Answer 1

well the sequence is not arithmetic as it doesn't change by the same amount each time

100, 80, 64 changes by -20 then - 16

so to check geometric look at the ratio of the terms.

Does

\[\frac{80}{100} = \frac{64}{80}\]

if yes, then you have the common ratio.

hope it helps

Answer 2

Thanks