Sec. 4-5: Applying Ratios to Probability

Getting a “TAIL” with one flip of a coin 1. Outcome: The result of a single trial of a probability experiment. Getting a “TAIL” with one flip of a coin

2. Event: The “desired effect” of a probability experiment. A “TAIL” or “HEAD” when flipping a coin. Simple Events: Result of a single trial. Compound Events: 2 or more simple events, like rolling an EVEN number on a die.

3. Sample Space: The SET of all possible outcomes of an experiment. {Tails, Heads}

P(x) = “Desired outcome” 4. Probability: P(x) Where x represents the event. P(x) = “Desired outcome” Sample Size Theoretical Probability: uses SAMPLE SPACES to determine probability. (You do NOT have to actually DO an experiment) P(“3”) = 1/6

Experimental Probability: An experiment must be done to determine the probability of an event. (Each outcome is considered to be equally likely.) P(a cancer eliminating pill) = ???

5. Complement: The opposite (probability). P(x) = 1 – P(x) if P(x) = .4 then P(x) = .6 if P(x) = 1/5 then P(x) = 4/5