Question

If you play 9 times in rock, paper, siccors, how many times would you expect to win? *

Answer 1

This gives {PPP, PPS, PPR, PSP, PSS, PSR, PRP, PRS, PRR}. By replacing player 1’s choice with scissors, then rock, the list of 9 outcomes becomes a complete list of 9 x 3 = 27 outcomes.

Answer 2

rock breaks scissors ... scissors cut paper ... paper covers rock
... or both show the same symbol ... tie

three equally likely outcomes ... win , lose , draw

you would expect to win 1/3 of the time