This document discusses solving problems involving joint variation. It begins by stating the learning objectives and targets, which are to solve problems involving variations and explain how to solve for unknown variable values. It then reviews that a statement of "a varies jointly as b and c" means the equation is a=kbc, where k is the constant of variation. An example problem is shown of finding a when b and c are given and the constant k is found using the initial values. Steps are provided to solve such problems: 1) write the correct variation equation, 2) use initial values to find k, 3) substitute k into the equation, 4) substitute all given values into the equation to find the unknown value. Several example problems are