Calculating Probabilities If you can calculate probabilities, you must set up a fraction (it can be turned into a percent later) The number of outcomes you want* The number of total possible outcomes The probability of an event happening = *AKA: “Favourable outcomes”

Calculating Probabilities 1 side with the number four 6 possible sides The probability of rolling a 4 on a normal die =

Calculating Probabilities 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 fewer vowels than consonants. True

Multiple events What if there is more than one event? You must find the probability of each individual event, and then multiply them together

The probability of both events happening is 1/12, or 8.33% Multiple events What are the odds of rolling the number two on a die, and then flipping a coin that lands on tails? Odds of dice roll: 1/6 Odds of coin flip: 1/2 1/6 x 1/2 = 1/12 The probability of both events happening is 1/12, or 8.33%