A2A | U1Q2 | Sequences & Series (ATA Unit Test)

• -4, -9, -19, -39, -79.

• -4, -7, -13, -25, -49.

• -4, -8, -15, -29, -57.

• -4, -10, -19, -37, -73.

Which formula can be used to represent the sequence below? {2, 5, 17, 65, 257, ...}

Which formula can be used to represent the sequence below? {-6, -3, 2, 9, 18, ...}

Find the sum of the first nine terms in the series below. {1 + 2 + 4 + 8 + 16 + ...}

• The sum of the first nine terms in the series is 31.

• The sum of the first nine terms in the series is 511.

• The sum of the first nine terms in the series is 120.

• Not enough information to find the sum of this series

Describe the sequence as arithmetic, geometric, or neither.

For arithmetic and geometric sequences, give the common difference or common ratio.

{3, -6, 12, -24, -48,...}

• Geometric

  Common Ratio: -2

• Arithmetic

  Common Difference: 9

• Neither

• Geometric

  Common Ratio: 2

Is the following sequence arithmetic, geometric, or neither.

For arithmetic and geometric sequences, give the common difference or common ratio. If neither, say it is NA.

{12, 6, 0, -6, -12,...}

This sequence is ​ (a)   and its common difference/ratio is ​ (b)  

• arithmetic
• -6
• geometric
• neither
• 6
• 2
• -2
• 1/2
• -1/2

Describe the sequence as arithmetic, geometric, or neither.

For arithmetic and geometric sequences, give the common difference or common ratio.

{3600, 1440, 576, 230.4,...}

• Geometric

  Common Ratio: 0.4

• Arithmetic

  Common Difference: 2160

• Neither

• Geometric

  Common Ratio: 0.5

Describe the sequence as arithmetic, geometric, or neither.

For arithmetic and geometric sequences, give the common difference or common ratio.

{600, -300, 100, -25,...}

• Geometric

  Common Ratio: -1/3

• Arithmetic

  Common Difference: -900

• Neither

• Geometric

  Common Ratio: -1/2