In math class, you learn how to find central angles of circles. But why is this skill important? This video explains how to find a central angle and its crucial role in civil engineering.

Main math topic: central angle of a circle
Other math topics: circumference, proportions, units conversion

The image at 05:55 (File:DBAG Baureihe 612 Neigebetrieb (612-009-1).jpg) is the courtesy of A. Gutwein. Distributed under CC BY-SA 3.0.