2 The probability of an event—the ratio of the number of favorable outcomes for the event to the total number of possible outcomes.EXAMPLE: When you flip a coin, there are two possible outcomes. The probability of getting a heads is 1:2 or
3 Sample space—list of all possible outcomes. When you roll a die, there are six possible outcomes: 1, 2, 3, 4, 5, or 6.What is the sample space of spinning this spinner?
4 When there are n outcomes and the probability of each one is 1 𝑛 , we say that the outcomes are equally likely.For example, when you roll a die, the 6 possible outcomes are equally likely because each outcome has a probability ofThe probability of an event is always between 0 and 1, inclusive. The closer a probability is to 1, the more likely it is to occur.
5 A die is rolled. Find each probability. a. rolling a 1 or 5 𝟐 𝟔 𝒐𝒓 𝟏 𝟑b. rolling an even number𝟑 𝟔 𝒐𝒓 𝟏 𝟐
6 A bowl contains 5 red chips, 7 blue chips, 6 yellow chips, and 10 green chips. One chip is randomly drawn. Find each probability.a. blue1 411 28b. red or yellow9 14c. not green
7 One method used for counting the number of possible outcomes is to draw a tree diagram. The last column of a tree diagram shows all of the possible outcomes.