Respuesta :
The series 1 + 3 + 9 + 27 is a geometric series because the common ratio is 3 option second is correct.
What is a sequence?
It is defined as the systematic way of representing the data that follows a certain rule of arithmetic.
As we know, the geometric series has a common ratio:
If a, b, c, d, e.....
is in the GP then,
b/a = c/b = d/c = and so on
We have a series:
0.1 + 0.3 + 0.5 + 0.7
0.3/0.1 ≠ 0.5/0.3
The above sequence is not a geometric series.
1 + 3 + 9 + 27
3/1 = 9/3 = 3
The above sequence is a geometric series.
19 + 17 + 15 + 13
17/19 ≠ 15/17
The above sequence is not a geometric series.
0.4 + 0.9 + 1.5 + 2.2
0.9/0.4 ≠ 1.5/0.9
The above sequence is not a geometric series.
Thus, the series 1 + 3 + 9 + 27 is a geometric series because the common ratio is 3 option second is correct.
Learn more about the sequence here:
brainly.com/question/21961097
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