Conditional probability in a tree diagram
I can calculate a conditional probability from a tree diagram.
Conditional probability in a tree diagram
I can calculate a conditional probability from a tree diagram.
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Lesson details
Key learning points
- A tree diagram can be used to calculate conditional probabilities
- A tree diagram can be used to calculate conditional probabilities involving sets of events
- Tree diagrams allow us to identify which events are mutually exclusive
- Tree diagrams can be used to identify which events are independent
Keywords
Probability - The probability that an event will occur is the proportion of times the event is expected to happen in a suitably large experiment.
Probability tree - Each branch of a probability tree shows a possible outcome from an event or from a stage of a trial, along with the probability of that outcome happening.
Independent events - Event A is independent of event B if the probability of event A occurring is not affected by whether or not event B occurs.
Mutually exclusive - Mutually exclusive events have no outcomes in common.
Common misconception
When pupils construct probability trees for scenarios where two marbles are removed from a bag, they may mistakenly subtract 2 from the denominators of the probabilities instead of 1.
Even though two marbles are removed from the bag at once, you can think of it at choosing one marble and then immediately choosing a second marble. At the end of the process, two marbles have been removed.
To help you plan your year 11 maths lesson on: Conditional probability in a tree diagram, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 11 maths lesson on: Conditional probability in a tree diagram, download all teaching resources for free and adapt to suit your pupils' needs.
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Lesson video
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Starter quiz
6 Questions
Exit quiz
6 Questions
$$x$$ -
0.2
$$y$$ -
0.1
$$z$$ -
0.7
