# Probability (Unit 5) Is the likelihood or chance of an even occurring.

## Presentation on theme: "Probability (Unit 5) Is the likelihood or chance of an even occurring."— Presentation transcript:

Probability (Unit 5) Is the likelihood or chance of an even occurring.
Favourable Outcomes Total Possible Outcomes What is the probability of rolling the number 2 on a dice? How many favourable outcomes? How many possible outcomes? Place these numbers into the fraction above…

How to express probability
Probability can be written in 3 ways... As a fraction = 1/6 As a decimal = 0.16 As a percent 0.16 x 100% = 16% How often will the number 2 show up when rolled?

Determine the probability
First you must find the possible outcomes (total) and then the favourable outcomes (what you’re looking for). Then place them into the probability equation. Rolling an even number on a dice? Pulling a red card out from a deck of cards? Using a four colored spinner to find green? Selecting a girl from your class? Favourable Outcomes Total Possible Outcomes

Determine the probability
A cookie jar contains 3 chocolate chip, 5 raisin, 11 Oreos, and 6 almond cookies. Find the probability if you were to reach inside the cookie jar for each of the cookies above. Type of Cookie Chocolate Chip Raisin Oreo Almond Fraction Decimal Percent Ratio

Determine the probability
Page 163: # 3ab, 5, 7 Page 164: # 9

Organized Outcomes Independent Events:
The outcome of one event has not effect on the outcome of another event Example: ROCK PAPER SCISSOR Tails Head

Organized Outcomes Sample Space:
All possible outcomes of an experiment What is the probability of Paper/Head? What is the probability of tails showing up? Sample Space Head Tail Rock Paper Scissor

“Tree Diagram” to represent Outcomes
H T Coin Flip R P S R P S Rock, Paper, Scissor H, Rock T, Rock H, Paper T, Paper H, Scissor T, Scissor Outcome

“Spider Diagram” to represent Outcomes
Rock Rock Paper Paper Scissor Scissor

Organized Outcomes You can find the sample space of two independent
events in many ways. Chart Tree Diagram Spider Diagram Your choice, but showing one of the above illustrates that you can find the favourable and possible outcomes for probability.

Organized Outcomes Page 169: # 5, 8 Page 170: # 9, 10

Probabilities of Simple Independent Events
Random: an event in which every outcome has an equal chance of occurring. A school gym has three doors on the stage and two back doors. During a school play, each character enters through one of the five doors. The next character to enter can be either a boy or a girl. Use a “Tree Diagram” to determine to show the sample space. Then answer the questions on the next slide!

Probabilities of Simple Independent Events
Random: an event in which every outcome has an equal chance of occurring. See Page 172 for your “Tree Diagram” of the school gym doors!

Using a Table to DETERMINE Probabilities
How to determine probabilities: Use “p” (or any other letter as the variable to represent what you’re looking for) and divide it by “t” the total outcomes. Then multiply your answer by 100%. Equation stays the same: p/t x 100% Use your results from the “tree diagram” of the gym doors and place them into a table. Then determine the probabilities for the scenarios on the next slide!

Using a Table to DETERMINE Probabilities
How to determine probabilities: p/t x 100% Back Left (BL) Back Right (BR) Left Stage (LS) Centre Stage (CS) Right Stage (RS) Boy BBL BBR BLS BCS BRS Girl GBL GBR GLS GCS GRS Determine the probability for the scenarios below... 1. Of a boy using any right door? 2. Of anyone (boy or girl) using a stage door? 3. Of a girls using any of the doors?

Determine Probabilities
Page 175: # 6, 8 Page 176: # 13

Applications of Independent Events
Use Tree Diagrams, Charts or other graphic organizers to solve probability problems. How can you win at the game of “Sit & Save?” RULES: Stand up at the beginning of the round. Two dice are rolled each round. You may collect the sum of your dice as long as a “6” does NOT appear. A “6” means all numbers before are cancelled and you get zero for that round. After each roll you have two choices Continue standing and roll again…hoping for no “6” Sit and collect your total points!

Applications of Independent Events
How can you win at the game of “Sit & Save?” Who had the highest score? What is the possibility of a 6 appearing with 2 dice? (sample data) Use the numbers above for each player to find who had the best probability (percent) of not rolling a 6. Student Names Round 1 Round 2 Round 3 Round 4 TOTAL

Interpret Outcomes Use Tree Diagrams, Charts or other graphic organizers to solve probability problems. What are the 2 independent events? What is the probability of the sum of these 2 events ending up to total “4”… What is the probability of outcome having one 3 appear?

Interpret Outcomes What is the probability of red appearing?
What is the possibility of a black and green appearing? What is the possibility of both events being two syllable words appearing?

Interpret Independent Outcomes
Page 181: # 6, 7 Page 182: # 9

Theoretical vs. Practical Probabilities
What are the chances of a boy and girl picking the same number from Try this 10 times and tally your results (Practical) . Then compare to your “theoretical answer.” Practical Boy Girl Theoretical 1 2 3 4 5 Boy B1 B2 B3 B4 B5 Girl G1 G2 G3 G4 G5

The expected probability of an event occurring.
Theoretical vs. Practical Probabilities What are the chances of a boy and girl picking the same number from Try this 10 times and tally your results (practical) . Then compare to your “theoretical” answer. Practical The probability of an event occurring based on experimental results. Boy Girl The expected probability of an event occurring. Theoretical 1 2 3 4 5 Boy B1 B2 B3 B4 B5 Girl G1 G2 G3 G4 G5