Geometric and Arithmetic Sequence

Carey is organizing her books and putting them on shelves. She put 2 books on the first shelf, 8 books on the second shelf, 32 books on the third shelf, and 128 books on the fourth shelf. What kind of sequence is this?

• Geometric

• Arithmetic

• Both

• Neither

Is this sequence arithmetic, geometric, or neither?
{26, 22, 18, 14, ...}

• Arithmetic

• Geometric

• Neither

What is the 38th term of this sequence?
{26, 22, 18, 14, ... }

• -4

• 10

• -122

• 174

What is the common ratio of this sequence?
{2, 10, 50, 250, ... }

• 1,250

• 5

• 10

• 50

• Arithmetic

• Geometric

Answer explanation

Percentages are almost always Geometric.

Is this sequence Arithmetic, Geometric, or Neither?
{14, 22, 30, 38, .. }

• Arithmetic

• Geometric

• Neither

Find the 10th term of this sequence:
{96, 48, 24, 12, ... }

• 3/16

• 1/2

• 6

• 3

An auditorium has 80 rows of seats and the number of seats per row increases at a constant rate.  If there are 32 seats in the 8th row, and 68 seats in the 20th row, how many seats are in the last row?

• 240

• 248

• 272

• 320

Which lists four consecutive terms of an arithmetic sequence?

• 1, 4, 9, 16, ...

• 3, 10, 17, 24, ...

• 1, 2, 4, 8, ...

• -5, 6, 10, 13, ...

What is a₅ in the sequence defined as follows?
a_n = 5 ⋅ 2^(n-1) 

• a₅ = 160

• a₅ = 40

• a₅ = 10

• a₅ = 80