Which of the following is an arithmetic sequence? O 4, 8, 12, 16, 20, ...
O 2, 4, 8, 16, 32, ...
O 4, 9, 16, 25, 36, ...
O 1, 1, 2, 3, 5, 8, 13, ...

Here are a few lists of numbers:

3, 5, 7 ...

21, 16, 11, 6 ...

1, 2, 4, 8 ...

Step-by-step explanation:

Ordered lists of numbers like these are called sequences. Each number in a sequence is called a term.

3,3,3, comma5,5,5, comma7,...7,...7, comma, point, point, point

\uparrow↑\uparrow\uparrow↑\uparrow\uparrow↑\uparrow

\footnotesize 1^\text{st}\text{ term}1

st

 term1, start superscript, start text, s, t, end text, end superscript, start text, space, t, e, r, m, end text\footnotesize 2^\text{nd}\text{ term}2

nd

 term2, start superscript, start text, n, d, end text, end superscript, start text, space, t, e, r, m, end text\footnotesize 3^\text{rd}\text{ term}3

rd

 term3, start superscript, start text, r, d, end text, end superscript, start text, space, t, e, r, m, end text

Sequences usually have patterns that allow us to predict what the next term might be.

For example, in the sequence 3, 5, 7 ..., you always add two to get the next term:

\footnotesize\maroonC{+2\,\Large\curvearrowright}+2↷start color #ed5fa6, plus, 2, \curvearrowright, end color #ed5fa6  \footnotesize\maroonC{+2\,\Large\curvearrowright}+2↷start color #ed5fa6, plus, 2, \curvearrowright, end color #ed5fa6  

3,3,3, comma  5,5,5, comma  7,...7,...7, comma, point, point, point

72 is the answer to this problem