How to determine a mixed strategy according to the Germeier criterion with respect to the payoff matrix?

Question

Mathematics

Hello. Help with the question of finding a mixed strategy in the theory of operations research (section - theory of games with nature).
We are given the Germeier matrix (where the rows are the player's pure strategies, and the columns are states of nature, a are payoffs, q are the probabilities of some state of nature occurring).

According to the Germeier criterion applicable to this matrix, I found a pure strategy. But how to find a mixed strategy, that is, an m-dimensional vector that would give the best result?