Final answer:
An arithmetic series converges if the common difference is less than 1 in absolute value, causing the terms to get smaller and the sum to approach a finite value. For example, the series 3, 1, -1, -3, ... is convergent because the terms are decreasing and approaching 0 as n increases.
Step-by-step explanation:
An arithmetic series converges under certain conditions. Specifically, an arithmetic series will converge if the common difference (denoted as 'd') is less than 1 in absolute value. This means that the terms of the series are getting smaller and smaller as n (the number of terms) increases. As a result, the sum of the series will approach a finite value as n approaches infinity.
For example, the arithmetic series 3, 7, 11, 15, ... has a common difference of 4. This series is divergent because the terms are increasing as n increases. However, the arithmetic series 3, 1, -1, -3, ... has a common difference of -2. This series is convergent because the terms are decreasing and approaching 0 as n increases.