Mathematically challenged? Your calculator won't help much either, if you don't know how to use it. Here are the basic calculator keystrokes you'll need to solve all levels of navigation problems, from "60 D Street" to celestial sight reductions.
USPS Guides are available to members and the public at various marine supply stores, and also directly from United States Power Squadrons Headquarters by calling 1-888-FOR-USPS between 8:00AM and 4:30PM ET Monday through Friday, or on-line via the United States Power Squadrons Ship's Store. Visa, MasterCard, Discover, and American Express are accepted. These guides are also available to USPS members through their Squadron Educational Officer.