Varsity Tutors
Varsity Tutors: Hotmath: Sequences and Series
Hotmath provides 20 practice problems relating to sequences and series. Each of the practice problems include a step-by-step guide for solving.
University of Baltimore
University of Baltimore: Geometric Mean
A complete definition of geometric mean in the statistical concept of the word. The discussion includes several examples of how geometric means are calculated and how/where they are useful. Written by Dr. Hossein Arsham.