Mathematics for IGCSE & O level - Probability (Section 6 - No. 41)
What is the key difference between independent and dependent events in terms of calculating probabilities?
For dependent events, you add probabilities; for independent, you multiply.
For independent events, the probabilities of the second event are changed by the first event; in dependent they aren't.
For independent events, the outcome of the first event affects the outcome of the second event; for dependent events it doesn't.
The probabilities on the second set of branches in a tree diagram are the same for independent events and different for dependent events.
Shpjegimi
In dependent events, the probability of the second event depends on the outcome of the first, thus the branches on the tree diagram will have different probabilities for dependent events.