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counting and probability intermediate

Problem

Matt and Ryan are playing an exciting round of Rock Paper Scissors: The Collectible Card Game. Matt is convinced that Rock can beat anything, so his deck consists only of 8 Rock cards. Ryan's deck consists of 5 Paper cards and 3 Scissors cards. In the game, Matt randomly selects 3 cards from his deck and places them on the table. Ryan then randomly selects 3 cards and places one on each of Matt's cards. If Rock beats Scissors, Scissors beats Paper, and Paper beats Rock, then what's the probability that Ryan beats Matt in a landslide by choosing 3 Paper cards in a row?
Solution
There are equally likely ways for Ryan to pick 3 of his 8 cards to play. There are are ways for those 3 cards to be 3 of his 5 paper cards. So, the probability that he picks 3 paper cards is .
Final answer
\frac{5}{28}