books.google.com - Employing a practical, "learn by doing" approach, this first-rate text fosters the development of the skills beyond the pure mathematics needed to set up and manipulate mathematical models. The author draws on a diversity of fields — including science, engineering, and operations research — to provide...http://books.google.com/books/about/An_Introduction_to_Mathematical_Modeling.html?id=adf515kSDOkC&q=normally+distributed&utm_source=gb-gplus-shareAn Introduction to Mathematical Modeling