Calculate probabilities of independent events

In this lesson, we will learn how to calculate probabilities of outcomes for independent events from tree diagrams

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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.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.

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.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

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Worksheet

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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.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
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.

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.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
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.

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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