Probability of Rock Paper Scissors

Name:

Probability of Rock Paper Scissors

Write the players’ names in the chart below. Record what each player “throws”
in each round and then write which player wins.

Example: Player 1 throws Rock, Player 2 throws Paper. You write down Rock,
Paper, and then Player 2 wins. You must write down all ties!

Player :______________ Player 2: _____________ Winner:

Round 1

Round 2

Round 3

Round 4

Round 5

Round 6

Round 7

Round 8

Round 9

Round 10

Round 11

Round 12

Round 13

Round 14

Round 15

Round 16

Round 17

Round 18

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(1) After you complete the above data table write the sample space AND tree
diagram of the possible outcomes below. Remember, the first event is what the
first player does and the second event is what the second player does. The first
of each is done for you:

Sample Space: (complete 2 more Tree Diagram: (complete 2 more trees)
groupings)
Rock(P1)
Rock(P1), Rock(P2)
Rock(P1), Paper(P2) Rock(P2) Paper(P2) Scissors(P2)
Rock(P1), Scissors(P2) [tie] [P2 win] [P1 win]

Label the outcomes on the tree diagrams above as a win for the first player,
second player, or a tie.

(2) How many outcomes does the game have?

(3) What is the theoretical probability that the first player should win?
(fraction, decimal, and percent)

(4) What is the theoretical probability that the second player should win?
(fraction, decimal, and percent)

(5) Is this game fair? Do both players have an equal opportunity to win the
game? EXPLAIN.

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(6) What is the experimental probability that the first player won? (fraction,
decimal, and percent)

(7) What is the experimental probability that the second player won? (fraction,
decimal, and percent)

(8) Compare the theoretical probability and experimental probability of one player
(you choose which player) throwing rock, paper, and scissors.

Rock: theoretical= experimental=

Paper: theoretical= experimental=

Scissors: theoretical= experimental=

(9) Write a couple sentences comparing the experimental probability to the
theoretical probability. What did you find and why do you think it happened?

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