Approachable solutions for three official GRE mathematics subject tests--the GR1268, GR0568, and GR9768. The booklet contains 140 pages of solutions and an eighteen-page glossary.The purpose of this booklet is simple: To help students study. Solutions have enough detail to aid those struggling, and the design is such that it is also suitable as a reference. All major theorems are stated either within the main text, glossary, or both. In particular, great pains were taken to include theorems from Calculus and below.Everything is written from an intuitive perspective. Graphs are used extensively, and geometric arguments are frequently utilized. Constructive solutions are given whenever possible.