# Find probabilities from frequency trees

In this lesson, we will learn how to use frequency trees to find probabilities including revision on how to draw frequency trees given some information.

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Some children were asked if they owned a cat or a dog. A child is chosen at random. Calculate the probability that a child who owns a cat is chosen.

1/4

Q2.Some children were asked if they owned a cat or a dog. A child is chosen at random. Calculate the probability that a child who owns a dog or a cat is chosen.

2/4

Q3.This Venn diagram shows the number of students who study art, history and geography. Calculate P (Art ∩ Geography)

3/4

Q4.This Venn diagram shows the number of students who study art, history and geography. Calculate P(not history).

4/4

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Some children were asked if they owned a cat or a dog. A child is chosen at random. Calculate the probability that a child who owns a cat is chosen.

1/4

Q2.Some children were asked if they owned a cat or a dog. A child is chosen at random. Calculate the probability that a child who owns a dog or a cat is chosen.

2/4

Q3.This Venn diagram shows the number of students who study art, history and geography. Calculate P (Art ∩ Geography)

3/4

Q4.This Venn diagram shows the number of students who study art, history and geography. Calculate P(not history).

4/4

# Video

Click on the play button to start the video. If your teacher asks you to pause the video and look at the worksheet you should:

• Click "Close Video"
• Click "Next" to view the activity

Your video will re-appear on the next page, and will stay paused in the right place.

# Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Find probabilities from frequency trees

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Here is some information regarding a sign language course taken by some students in year 10 and year 11. A student is randomly selected. What is the probability that they are in year 11?

1/3

Q2.Here is some information regarding a sign language course taken by some students in year 10 and year 11. A student is randomly selected. What is the probability that they passed the course?

2/3

Q3.Here is some information regarding a sign language course taken by some students in year 10 and year 11. A student is randomly selected. What probability scenario is represented by the fraction 50 out of 150?

3/3

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Find probabilities from frequency trees

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Here is some information regarding a sign language course taken by some students in year 10 and year 11. A student is randomly selected. What is the probability that they are in year 11?

1/3

Q2.Here is some information regarding a sign language course taken by some students in year 10 and year 11. A student is randomly selected. What is the probability that they passed the course?

2/3

Q3.Here is some information regarding a sign language course taken by some students in year 10 and year 11. A student is randomly selected. What probability scenario is represented by the fraction 50 out of 150?

3/3

# Lesson summary: Find probabilities from frequency trees

## Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:
Jog

On the spot:
Dance