Probability

Probability

SI Week 7

Agenda

• Opening Activity: Probability

• Main Activity: Class Led Lesson

• Closing Activity: Exit Ticket/Mini Quiz

Opening Activity

Go on the Padlet and select a vocabulary term that you have learned in lesson 3. You can use your textbook, notes, or class slides for this. Create a sticky note and include the term and definition. Try not to have repeats :)

https://padlet.com/ajimenez2081/2sif1hpy94onid09

Main Activity

We will be having a class-led mini-lesson. You are leading the class. I'm only here to ask questions as if I have no idea what probability is.

Fill in the Blank

First up: Terminology!!

Define Sample Space

Open Ended

Give me an example of Sample Space

Multiple Select

What are the three ways to represent a sample space

• tree diagram

• list possible outcomes

• venn diagram

• simple random sampling

• with an experiment

Fill in the Blank

Define Event

Open Ended

Give me an example of an Event

Multiple Choice

Probabilities are between zero and one.

What does P(A) = 0 represent?

• event A can always happen

• event A can never happen

• event A is equally likely to occur or not to occur.

Multiple Choice

What does P(A) = 1 represent

• Event A can never happen

• Event A is equally likely to occur or not to occur.

• Event can always happen

Multiple Choice

What does P(A) = 0.5 represent?

• Event A is equally likely to occur or not to occur.

• Event A will never occur

• Event A will always occur

So far we know the following

• Sample Space: is the set of all possible outcomes.

• Three ways to represent a sample space are: to list the possible outcomes, to create a tree diagram, or to create a Venn diagram.

• Event is any combination of outcomes. Upper case letters like A and B represent events.

• P(A) = 0 means the event A can never happen. 

• P(A) = 1 means the event A always happens. 

• P(A) = 0.5 means the event A is equally likely to occur or not to occur.

Open Ended

The conditional probability of A given B is written P(A|B). P(A|B) is the probability that event A will occur given that event B has already occurred. What is the formula for conditional probability?

Take a moment to familiarize yourself with the formula if you got the previous question wrong.

Fill in the Blank

The complement of event A is denoted A′ (read "A prime"). A′ consists of all outcomes that are NOT in A. For example, let S = {1, 2, 3, 4, 5, 6} and let A = {1, 2, 3, 4}. Then, A′ =

S is the whole number starting at 1 & less than 20. Event A = the even numbers and event B = numbers greater than 13

• S = _____________________________ 

• A = _____________________, B = ____________

• P(A) = _____________, P(B) = ________________

• A AND B = ____________________, A OR B = __________

• P(A AND B) = _________, P(A OR B) = _____________

• A′ = _____________, P(A′) = _____________

• P(A) + P(A′) = ____________