How can you work out the probability of two events happening using a tree diagram?

2 years ago


4 Replies




Chadrick Lowe

4 Answers

Dhanush Vydyam

We multiply the probabilities of those events


If for example we are given the following probabilities:

In Basket 1, P(Apple) = 0.25 and P(Pear) = 0.75

In Basket 2, P(Apple) = 0.65 and P(Pear) = 0.35

The probability of picking an apple from Basket 1 and a pear from basket 2 would be = 0.25*0.35

Ali Sadreddin

You multiply probabilities when you move across a tree diagram branch and add probabilities when moving up and down the branches. Conditional probabilities work slightly different. You will need to engage Bayes's theorem

Emily Uden

Multiply across the branches of the sequence you require

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A probability tree indicates probabilities and some conditional probabilities for combinations of events. 

Example: Flipping a biased coin twice. 

Event 1- first coin flip; Event 2- second coin flip

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