



 
Hi kk, A probability tree shows every possible outcome of the the chip toss. The first red chip will show either an A or a B (so far 2 different outcomes). For each of those outcomes, the second red chip can also either be an A or a B (so now we're up to 4 different outcomes: AA, AB, BA, BB). For each of the four possible outcomes on the first two chips, we also have that the blue chip can be either A or B. So there are 8 possible outcomes in total, as shown by the 8 branches in this tree: Each branch in the tree shows one of the possible results of the chip toss. For example, the branch I have circled shows the result when the first red chip is an A, the second red chip is an A, and the blue chip is a B. In this case, player 1 would win. How many other branches give a win for player 1? How many branches result in player 2 winning? Can you take it from here? Haley  


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