Arithmetic Sequences and Series

Common Difference

100

Find the common difference 17,12,7

-5

200

Find the common difference -129,-98,-67

31

300

Find the common difference 244,187,130

-57

400

Find the common difference 7,11,15

4

500

Find the common difference -10,-5,0

5

Explicit and Recursive

100

Find the Recursive formula of the arithmetic sequence 12, 21, 30, ...

A₁= 12, A_n=A_n-1 + 9

200

Find the explicit formula for 12, 21, 30, ...

An = 9n + 3 

300

Find the recursive formula of the arithmetic sequence 29, -1, -31, ...

A₁= 29, A_n=A_n-1 - 30

400

Find the recursive formula -42, -39, -36, ...

A₁ = -42, A_n= A_n-1 + 3

500

Find explicit formula -16.3,-18.4,-20.5....

an=-16.3+(n-1)-2.1

Find the nth term

100

Find the 38th term of the arithmetic sequence -29,-2,25...

970

200

Find the 68th term of the arithmetic sequence 25,17,9....

-511

300

Find the 27th term of the arithmetic sequence 5,8,11,14...

83

400

Find the 16th term of the arithmetic sequence 17,12,7...

-58

500

Find the 14th term of the arithmetic sequence 244,187,130..

-497

Sum of the Arithmetic series

100

Find the indicated sum for the first 8 term of the arithmetic series 8 + 12 + 16 + 20 + ... + 48

280

200

Find the number of terms in the series 4 + 9 + 14 + ... + 79

16 terms

300

Find the sum of the first 10 terms of an arithmetic series with a first term of 2 and a common difference of 3. 

S₁₀ = 155

400

Find the 19th partial sum of -19+23+65+....

6821

500

Find the indicated sum of the arithmetic series -10 - 6 - 2 + ... + 22

156