Topics
15. Probability
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15.03 Types of events

Lesson
Practice
Lesson

Are you ready?

What  outcomes  can happen when you roll a die? Can you make a list? Which outcomes are odd? Which outcomes are even?

Examples

Example 1

A six-sided die is rolled.

An image of a six sided die.
a

List all the possible outcomes from rolling the die:

⬚, \,2, \,⬚, \,⬚, \,5, \,6

Worked Solution
Create a strategy

Think of the numbers can be rolled on a standard six-sided die.

Apply the idea

The numbers 1 to 6 can be rolled on a six-sided die.

1, \,2, \,3, \,4, \,5, \,6

b

What is the chance that a 6 is rolled?

A
Likely
B
Unlikely
Worked Solution
Create a strategy

Use the list of possible outcomes in part (a).

Apply the idea

Each number in the list appears once on a die. So, the cance of rolling a 6 is 1 out of 6 which is a very low or unlikely.

The answer is option B.

Idea summary

A six sided die has 1, 2, 3, 4, 5, and a 6 on it only. So those numbers are the only possible outcomes when rolling a die.

Types of events

Sometimes there are events that can have an impact on others. This video shows us what this means.

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Examples

Example 2

If the following spinner is spun and lands on a star twice in a row, will this affect the chance of the spinner landing on a star on the third spin?

A spinner with a pig, ball and star on it. Ask your teacher for more information.
Worked Solution
Create a strategy

The outcome of a spinner gives random results that are not affected by the previous spin.

Apply the idea

Even if we spun the spinner and it lands on a star twice, the result on the third spin is still random.

This means the first two spins will not affect the chance of the spinner landing on a star on the third spin.

Idea summary

When spinning a spinner, the results of the previous spins do not affect the next spin. This is also true for tossing a coin or rolling a die.

Events that happen at the same time

Some types of experiments mean that only one outcome can happen in each trial. This video shows us what this means.

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Examples

Example 3

A coin is tossed. Is it possible for the following two outcomes to happen at the same time?

  1. The coin lands on heads

  2. The coin lands on tails

Worked Solution
Apply the idea

No, because a coin heads and tails are on different sides of the coin and a coin can't land on both sides at once.

Idea summary

Flipping a coin will always give one possible outcome:

  1. The coin lands on heads

  2. The coin lands on tails

Different outcomes

Sometimes in an experiment, there are multiple things that could happen as an outcome. For example, if you roll a die then you could get a 3, and an odd number at the same time. This video shows us more about this.

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Examples

Example 4

A dog is randomly selected from the group of dogs shown.

This image shows 10 different dogs. Ask your teacher for more information.

Which two outcomes could happen at the same time?

A
Selecting a dog that is running
B
Selecting a dog with something in its mouth
C
Selecting a dog with its tongue out
D
Selecting a dog with spots
Worked Solution
Create a strategy

Based on the image, find the two events that are both happening in the same dog.

Apply the idea

There is one dog that is running with something on its mouth in the top right corner. So the events that could happen at the same time are options A and B.

Idea summary

Sometimes, the result of an experiment can impact the outcome of the next result. Other times, it doesn't matter what the outcome is, it doesn't have any impact on other results.

Outcomes

MA3-19SP

conducts chance experiments and assigns probabilities as values between 0 and 1 to describe their outcomes

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