Year 11
Higher

Calculate probabilities of dependent events

Year 11
Higher

Calculate probabilities of dependent events

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Lesson details

Key learning points

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

Licence

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3 Questions

Q1.
Probability of a dependent event is also called?
Biased probability.
Correct answer: Conditional probability.
Mutually exclusive.
Random probability.
Q2.
Simon has drawn this probability tree for a question on dependent probability. What mistake has he made?
An image in a quiz
The fractions on each branch do not sum to 1.
The probabilities should be decimals.
Correct answer: The second part of the probability tree has incorrect probabilities.
Q3.
This tree diagram shows Amir taking red and blue sweets from a bag. He does not replace the sweet after he has taken one.
An image in a quiz
A
B
Correct answer: C
D

3 Questions

Q1.
Amy is going to pick 2 biscuits from a box. Some are chocolate and some are plain. The probability tree shows the probability information.
An image in a quiz
Correct answer: A
B
C
D
Q2.
James is also going to pick 2 biscuits from a box. Some are chocolate and some are plain. The probability tree shows the probability information.
An image in a quiz
A
B
Correct answer: C
D
Q3.
Here is a probability tree showing Amir taking red and blue sweets from a bag.
An image in a quiz
P(B,B)
Correct answer: P(B,R)
P(R,B)
P(R,R)