Calculating Probabilities If a set of events have an equal chance of occurring, it is possible to calculate probabilities. For example, you can calculate the probability of rolling a 4 on a die because the 4 has the same chance of occurring as the other numbers.

Calculating Probabilities If you can calculate probabilities, you can use this simple method: The number of results you want The number of possible results The probability of an event happening =

Calculating Probabilities If you can calculate probabilities, you can use this simple method: 1 side with the number 4 6 possible sides The probability of rolling a 4 on a normal die =

Calculating Probabilities If you can calculate probabilities, you can use this simple method: 1 6 The probability of rolling a 4 on a normal die =

Calculating Probabilities Which of these statements are true about the word MATHEMATICAL? The probability of picking a vowel is 50 % because a letter picked is either a vowel or it isn’t. The probability of picking a vowel is 5 because there are 5 vowels out of 12 12 letters. False, there are less vowels than consonants. True

Calculating Probabilities This spinner represents all of class 6B How class 6b get to school Decide which of these statements are true. other walk bike car bus

Calculating Probabilities The chance of landing on a person who said bike or car is the same as landing on a person who walks. True The chance of getting “bike” is the same as getting “car” other walk bike False car bus

Calculating Probabilities The chance of getting “car” is 1 2 False The chance of getting car is 25 % other walk bike True car bus