arithmetic and geometric sequences

Which sequence is NOT an arithmetic sequence?

• -7, -13, -19, -25,...

• -10, -6, -2, 2,..

• 6, 8, 10, 12,...

• 3, 15, 75, 375,...

What is the common difference of the sequence 2, -1, -4, -7,...?

• -3

• -1

• -2

• 3

An arithmetic sequence is given below.

16, 13, 10, 7, ...

Which is the explicit formula for the n^th term a_n?

• a_n = -3n+19

• a_n = -5n+13

• a_n = 3n+13

• a_n = -5n+20

What is the 67^th term of the following arithmetic sequence.

13, 22, 31, 40, ...

• -445

• 67

• 625

• 607

What is the 76^th term of the following arithmetic sequence?

8, 14, 20, 26,...

• 76

• 452

• 458

• 476

Find a₂₀ in the arithmetic sequence: (Hint: Find explicit formula first)

5, 12, 19, 26...

• 145

• 144

• 142

• 138

Find the next three terms in the arithmetic sequence: -3, -8, -13, -18, ...

• -20, -24, -28
• -21, -25, -29
• -23, -28, -33
• -24, -29, -32

Find the 35th term in the arithmetic sequence: -10, -14, -18, -22, ...

• -216
• -148
• -146
• -150

Find a₂₆ in the arithmetic sequence: -15, -35, -55, -75, ...

• -515
• -490
• -535
• 460

Find the 25th term of the sequence if the first term is 5 and the sequence is increasing by $\frac{1}{2}$ .

• 18

• 17

• 15

• 14