What is the common ratio in the following geometric sequence?

2, 12
, 18
, 132
, . . .

(1 point)
Responses

4
4

14
Start Fraction 1 over 4 End Fraction

12
Start Fraction 1 over 2 End Fraction

−1.5

1 answer

To find the common ratio in a geometric sequence, you divide any term by the previous term.

Let's use the first two terms of the sequence you provided:

  • The first term \( a_1 = 2 \)
  • The second term \( a_2 = 12 \)

The common ratio \( r \) can be calculated as follows:

\[ r = \frac{a_2}{a_1} = \frac{12}{2} = 6 \]

Now, checking the next term \( a_3 = 18 \) from \( a_2 = 12 \):

\[ r = \frac{a_3}{a_2} = \frac{18}{12} = 1.5 \]

This does not match the previous calculation, indicating that the sequence is not consistent and is not a geometric sequence.

So, let's verify:

Next, check between \( a_3 = 18 \) and \( a_4 = 132 \):

\[ r = \frac{a_4}{a_3} = \frac{132}{18} = 7.3333 \ldots \]

This also does not yield a consistent ratio with other terms. We see that the sequence does not maintain a single common ratio throughout.

Thus, the common ratio you provided in the answer choices does not apply since this is not a consistent geometric sequence. If you were looking to identify a specific term in another context, please clarify and we can explore that!