Calculate probabilities of independent events

A lesson to calculate probabilities of outcomes for independent events from tree diagrams

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

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!

Question 1

Question 2

Question 3

Q1.Here is the first branch of a probability tree diagram.

1/3

Q2.Here is the first branch of a different probability tree diagram. What should the missing probability be?

2/3

Q3.This tree diagram shows Amir taking red and blue counters from a jar. He replaces the counter after he has picked one up.

3/3

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

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!

Question 1

Question 2

Question 3

Q1.Here is the first branch of a probability tree diagram.

1/3

Q2.Here is the first branch of a different probability tree diagram. What should the missing probability be?

2/3

Q3.This tree diagram shows Amir taking red and blue counters from a jar. He replaces the counter after he has picked one up.

3/3

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:

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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.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Calculate probabilities of independent events

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

Question 1

Question 2

Question 3

Q1.For the probability tree shown, which calculation will find the probability of red followed by blue happening?

1/3

Q2.The probability that Amy and Joe win a game of chess is shown in the tree diagram. Work out the probability that over 2 games Amy wins twice.

2/3

Q3.James draws this probability tree diagram to help him calculate probabilities of taking sweets from a bag. What assumptions has James made when completing this probability tree?

3/3

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Calculate probabilities of independent events

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

Question 1

Question 2

Question 3

Q1.For the probability tree shown, which calculation will find the probability of red followed by blue happening?

1/3

Q2.The probability that Amy and Joe win a game of chess is shown in the tree diagram. Work out the probability that over 2 games Amy wins twice.

2/3

Q3.James draws this probability tree diagram to help him calculate probabilities of taking sweets from a bag. What assumptions has James made when completing this probability tree?

3/3

Lesson summary: Calculate probabilities of independent events

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