# 7: Sums of Random Variables

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• 7.1: Sums of Discrete Random Variables
In this chapter we turn to the important question of determining the distribution of a sum of independent random variables in terms of the distributions of the individual constituents. In this section we consider only sums of discrete random variables, reserving the case of continuous random variables for the next section.
• 7.2: Sums of Continuous Random Variables
In this section we consider the continuous version of the problem posed in the previous section: How are sums of independent random variables distributed?

Thumbnail: Visual comparison of convolution. (CC BY-SA 3.0; Cmglee via Wikipedia)

This page titled 7: Sums of Random Variables is shared under a GNU Free Documentation License 1.3 license and was authored, remixed, and/or curated by Charles M. Grinstead & J. Laurie Snell (American Mathematical Society) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.