Question

Suppose the probability for A to win a game against B is 0.4. If A has an option of playing either a beet of 3 games" or a "best of five game" match against B, which option should A choose so that the probability of his winning the match is higher? No game ends in a draw.

Answer 1

The probability of $A$ to win is $0.4$

For a BEET of $3$ games The probability is $(0.4{)}^3=0.064$

For best of $5$ the probability is $\left(0.4\right)$

So the probability is higher in best of $5$ so he would choose it.