  The quantum probabilistic convergence in measurement, distinct from
mathematical convergence, is derived for indeterminate probabilities from the
weak quantum law of large numbers. This is presented in three theorems. The
first establishes the necessary bridge between ensemble theory and experiment.
The second analyzes the most important theoretical ensemble entity: the
eigen-projector of the relative frequency operator. Its physical meaning is the
experimental relative frequency. The third theorem formulates the quantum
probabilistic convergence, which is the final result of this investigation.
