Solve Normal form Nash eq. (pure and mixed), especially the probabilities

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can someone please help me to solve this question:

Consider the normal form game:

Normal form game

i) For Player 1 the strategy B is strictly dominated by C.

ii) For Player 2 the strategy E is strictly dominated by F.

iii) The game has 2 Nash eq. in pure strategies and further equilibrium in mixed strategies. In this third eq. player 1 chooses between A,B, and C according to the probabilities:

σA= __________, σB= ___________, σC= _____________.

and player 2 chooses between D,E and F according to the probabilities:

σD= __________, σE= ___________, σF _____________.

It would be nice if someone of you can help me to find the solution for the probabilities (Step iii), with a quick explanation. I only can solve a 2x2 matrix but have never done this for a 3x3 matrix.

And are the solutions for i) and ii) correct?

Thanks for helping me!

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Assuming that the numbers in the bimatrix are the payoffs to the players (as opposed to penalties on them), I believe your answers i) and ii) have the dominance the wrong way round. Each payoff to player $1$ in strategy B is strictly larger than the corresponding payoff in strategy C, so it's B that strictly dominates C, not the other way round.

Likewise, each payoff to player $2$ in strategy E is strictly larger than the corresponding payoff in strategy F, so E strictly dominates F.

Hint for solving iii):

Since strategy C is strictly dominated by strategy B for player $1$ it cannot appear with positive probability in any Nash equilibrium. Likewise, strategy F for player $2$ cannot appear with positive probability in any Nash equilibrium. You can therefore ignore those strategies entirely and obtain the Nash equilibria of the original $3\times3$ game by finding the Nash equilibria of the $2\times2$ game with bimatrix: \begin{array}{||c|c|} \hline &\text{D}&\text{E}\\ \hline \text{A}&6,12&4,8\\ \hline \text{B}&4,8&8,16\\ \hline \end{array}