# Arithmetic Series Formula Practice Problems

Solve each problem on paper then click the ANSWER button to check if you got it right.

Problem 1: Find the sum of the first 300 natural or counting numbers.

\color{red}45,150

Problem 2: What is the sum of the first 100 positive odd numbers?

\color{red}10,000

Problem 3: What is the sum of the first 100 positive even numbers?

\color{red}10,100

Problem 4: Find the sum of the first 64 terms of the arithmetic series below.

3 + 9 + 15 + 21 + …

\color{red}12,288

Problem 5: Find the sum of the first 50 terms of the arithmetic series below.

- 5 + \left( { - 8} \right) + \left( { - 11} \right) + \left( { - 14} \right) + …

\color{red} - 3,925

Problem 6: Find the partial sum of the arithmetic series below.

7 + 12 + 17 + 22 + … + 187

\color{red}3,589

Problem 7: Find the partial sum of the arithmetic series below.

- 8 - 11 - 14 - 17 - … - 113

\color{red}-2,178

Problem 8: The 15th term of the arithmetic sequence is 33 and the 50th term is 103. What is the 79th partial sum of the arithmetic sequence?

\color{red}6,557

Problem 9: The 7th term of the arithmetic sequence is -19 and the 13th term is 35. What is the 30th partial sum of the arithmetic sequence?

\color{red}1,725

Problem 10: The 9th term of an arithmetic sequence is 57 while its 18th partial sum is 1,080. Find the sum of the first 31 terms of the sequence.