Pass Check: Tree Diagrams & Combined Events
Multiply along branches, add between separate branches, and check totals equal 1.
Branch
A line on a tree diagram showing one possible outcome and its probability.
With replacement
When an item is put back before the next selection, so probabilities stay the same each time.
Without replacement
When an item is not put back, so probabilities change for the next selection.
Conditional probability
The probability of an event happening given that another event has already happened.
Quick check
Mixed quiz
1. Which calculation finds P(A and B) for independent events A and B?
2. Which is a correct feature of tree diagrams without replacement?
3. Which represents the correct formula for conditional probability P(A|B)?
4. An object has a mass of 55 g and a volume of 22 cm^3. Calculate its density, to 2 decimal places.
5. An object has a mass of 70 g and a volume of 28 cm^3. Calculate its density, to 2 decimal places.
6. A train travels 120 km in 2 hours. Calculate its average speed.
7. Which unit is correct for density?
8. A train travels 140 km in 2 hours. Calculate its average speed.