General Sequences and Series
Arithmetic Sequences
Geometric Sequences
Series
Series
100

What is the difference between a sequence and a series?

A sequence is an ordered list of numbers, whereas a series is the sum of a given number of terms in a sequence.

100

In an arithmetic sequence, the first term is -4 and the common difference is -1/3. What is the 10th term? The nth term?

a10=-7

an=(-1/3)n-(11/3)

100

For the given sequence, find the common ratio

1/2, 2, 8, 32, ...


r = 4

100

Find the S5

an = 2n + 1   for the first 5 terms.

35

100

Is the following a geometric series?

3 + 12 + 21 + 30, ...

No, this is arithmetic

200

What is the difference between an arithmetic and a geometric sequence?

An arithmetic sequence is a sequence that has a common difference (the same number gets added each time).

A geometric sequence is a sequence that has a common ratio (the same number gets multiplied each time).

200

Given that a1 = 7 and the common difference is -2, find a6

a6 = -3

200

Write the formula for the given geometric sequence:

32, 16, 8, 4, ...

an = 64 (1/2) n

200

Evaluate the given series.

S10 = 365

200

Evaluate the given series:

S9 = 39,364

300

Find the sum of the following series:

2, 11, 20, 29, 38

100

300

For the given sequence, find the common difference and the 10th term.


9, 12, 15, 18, ...

d = 3

a10 = 36

300

Given that a1 = 3 and r = 2, find a6.

a6 = 96

300

The sum of the first 24 terms of the arithmetic sequence is 804. Find a24.

-1 + 2 + 5 + ...

a24=68

300

Find the sum of the first 12 terms of the geometric series:

486 + 162 + 54 +  ...

S12=728.99

400

What is the next number in the pattern?

1, -1/3, 1/9, -1/27, ...

1/81

400

Find the 12th term of a sequence that has a first term of 5 and a common difference of 7

a12 = 82

400

Given the formula for the geometric sequence, list out the first 5 terms:

an = (-2)n

-2, 4,-8,16,-32


400

Evaluate the following series:

a1 = 42, an = 146, n = 14

1316

400

Find the sum of the series 9+3+1+...

27/2 or 13.5

500

Write a formula for the given sequence:

-2, 6, -18, 54, ...

an = (2/3)(-3)n

500

Write the formula for the given arithmetic sequence:

-2, 2, 6, 10, 14, ...

an = 4n - 6

500

The sixth term of a geometric sequence is 1215 and the third term is 45. Find the first term and the common ratio.

a1=5 r=3

500

Find the sum of the following series:

2 + 7 + 12 + 17 + ... 52

297

500


-425/1024 or -0.415