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Conditional Probability

2.12 Probability HOME | Objectives | Probability Review | Probability tables | Two Way Tables | Risk & Relative Risk | Tree Diagrams | Conditional Prob | Distributions | Actual vs Normal | Normal Distribution | Inverse Normal | Revision


Conditional Probability

Review of finding conditional probability from Two-way tables.

Finding conditional probability using the Formula
P(A|B) = P(A n B) / P(B)

Class notes | Blank notes

Theta (new & old & workbook) Ex 22.06
NuLake EAS p137-140



Tree diagrams with conditional Probability

Solving conditional problems using Probability Trees. 

Selecting without replacement diagrams

Class notes | Blank notes

Theta (new & old & workbook) Ex 22.03


Probability tree practice

Mixed probability tree problems


Theta (new & old & workbook) Ex 22.03

Excellent conditional probability website (link to

Conditional probability works backwards in a probability tree


Conditional Overview   back to top

Dodgy Dave's letter company sends 35% of letters 'standard' and the rest by 'express'
14% of ALL letters were lost in 'standard' delivery
What is the probability of a letter being lost just in 'standard' delivery?

Form a probability tree

Fill in known probabilities


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