Geometric Sequence Formulas

In a geometric sequence, the 4th term is -12 and the 5th term is -24. Find the common ratio.

• 2

• -2

In the geometric sequence

2, 6, 18, n, 162, ..., what is the value of n?

• 54

• 90

• 24

• 36

which sequence has a common ratio of -2?

• 4, 8, 16, 32

• 4, -8, 16, -32

• 32, 16, 8, 4

• -32, 16, -8, 4

If the first term of a geometric sequence is 6 and its common ratio is 2, the next three terms are:

• 12, 24, 48

• 8, 10, 12

• 4, 2, 0

• 3, 6, 9

Write the explicit equation for the geometric sequence:

• t(n) = 3ⁿ

• t(n) = 2ⁿ

• t(n) = 5ⁿ

• t(n) = 4ⁿ

The next term of the geometric sequence

4, 16, 64, ...

is

• 256

• 132

• 120

• 150

What is the fifth term of the geometric sequence?

• 135

• 1875

• 1215

• 405

Find the 9th term in the following geometric sequence:

4, 8, 16, 32, ...

• 384

• 512

• 768

• 1,024

Write the explicit equation for the geometric sequence: 15, 45, 135, . . . ?

Write the explicit equation for the geometric sequence: