The Grand Rapids Community College Mathematics Department is pleased to announce that it will host its first Mathematics Seminar of 2018-2019 on **Wednesday, September 26, 3-4 p.m. in 114 Cook**.

Our speaker is GRCC Mathematics Instructor John Dersch.

The study of mathematics has the potential to delight participants with beauty and surprising relationships. This talk will attempt to capture a small piece of mathematical wonder by connecting two ideas that appear to have nothing in common. Some knowledge of algebra will be useful, but, as always, everyone is welcome and encouraged to attend.

Refreshments will be served at 2:45 p.m.

**Series and Probability DO Mix**

Suppose you start adding 1 + + + + ¼ and you just keep going. As you add more and more terms, your answers will approach a unique number. It’s easy to approximate this number, but finding its exact value is a historically famous and fascinating problem. This talk has two parts. In Part 1 we will show how Leonhard Euler first solved this famous problem in the 1730s. Part 2 reveals an unexpected appearance of Euler’s solution in our search for the answer to a question involving probability and relatively prime numbers.