Frequently, various energy sources are used simultaneously in electric vehicles, smart grids, wind farms, among others, and usually boost power converters are interconnected to match impedance. However, the average output voltage level and the output voltage ripple are factors that directly impact the whole system's efficiency, useful life, component degradation, power quality, to name a few. Such analysis is complicated by the number of stages, synchronization, and conduction mode, and related research has been limited to interconnection issues, voltage gain, maximum power point tracking, and so on. In this paper, formulations for the average output voltage and the output voltage ripple are presented. These formulas can be used if overall boost stages operating either in continuous or discontinuous conduction mode, and their triggering is either phase-shifted or simultaneous. The formulations are validated by specialized software.