# Conditional probability from a two-way table

In this lesson, we will interpret two-way tables and find conditional probabilities from them.

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

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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.There are 10 counters in a bag. 4 counters are green and 6 counters are blue. Two counters are selected at random. If you want to calculate the probability that both are green, what calculation should you do?

1/3

Q2.There are 10 counters in a bag. 4 counters are green and 6 counters are blue. Two counters are selected at random. Calculate the probability that you get one of each colour.

2/3

Q3.There are 10 counters in a bag. 4 counters are green and 6 counters are blue. Two counters are selected at random. Calculate the probability that you get at least one blue.

3/3

#### 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.There are 10 counters in a bag. 4 counters are green and 6 counters are blue. Two counters are selected at random. If you want to calculate the probability that both are green, what calculation should you do?

1/3

Q2.There are 10 counters in a bag. 4 counters are green and 6 counters are blue. Two counters are selected at random. Calculate the probability that you get one of each colour.

2/3

Q3.There are 10 counters in a bag. 4 counters are green and 6 counters are blue. Two counters are selected at random. Calculate the probability that you get at least one blue.

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.

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

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

# Conditional probability from a two-way table

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

Q1.The two-way table shows information about year 7 and 8 students and their participation in some school clubs. How do you find the total number of students?

1/3

Q2.The two-way table shows information about year 7 and 8 students and their participation in some school clubs. What is the probability that two students picked at random attend debate club?

2/3

Q3.The two-way table shows information about year 7 and 8 students and their participation in some school clubs. What is the probability that two students picked at random attend chess club and one is in year 7 and the other in year 8?

3/3

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

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

# Conditional probability from a two-way table

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

Q1.The two-way table shows information about year 7 and 8 students and their participation in some school clubs. How do you find the total number of students?

1/3

Q2.The two-way table shows information about year 7 and 8 students and their participation in some school clubs. What is the probability that two students picked at random attend debate club?

2/3

Q3.The two-way table shows information about year 7 and 8 students and their participation in some school clubs. What is the probability that two students picked at random attend chess club and one is in year 7 and the other in year 8?

3/3

# Lesson summary: Conditional probability from a two-way table

## Time to move!

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

For 5 mins...

Move around:
Walk

On the spot:
Dance