Consider the geometric sequence: 5, 15, 45, 135, 405, …. What is the common ratio?
A) The common ratio is three-fifths.
B) The common ratio is five-thirds.
C) The common ratio is 3.
D) The common ratio is 5.
C) The common ratio is 3.
To find the common ratio in a geometric sequence, you divide any term by the previous term. For example, 15 divided by 5 is 3, 45 divided by 15 is 3, and so on. This consistent ratio of 3 between consecutive terms indicates that the common ratio is 3.