Study Notes
Probability is the chance or likelihood of an event happening, expressed as a fraction, decimal, or percentage. It ranges from 0 (impossible event) to 1 (certain event).
- Probability — the chance or likelihood of an event happening. Example: Probability of getting heads when tossing a coin.
- Relative Frequency — the number of times an event occurs divided by the total number of events. Example: If a spinner lands on blue 20 times out of 50 spins, the relative frequency is 20/50.
- Mutually Exclusive Events — events that cannot happen at the same time. Example: Rolling a die and getting either a 2 or a 5.
- Independent Events — events where the outcome of one does not affect the other. Example: Tossing two separate coins.
Exam Tips
Key Definitions to Remember
- Probability is the chance of an event happening.
- Relative frequency is an estimate of probability based on past data.
- Mutually exclusive events cannot occur simultaneously.
- Independent events do not affect each other's outcomes.
Common Confusions
- Confusing mutually exclusive events with independent events.
- Misinterpreting probability values as percentages instead of fractions or decimals.
Typical Exam Questions
- What is the probability of rolling a 6 on a die? Answer: 1/6
- If a coin is tossed twice, what is the probability of getting two heads? Answer: 1/4
- What is the probability of drawing a red card from a standard deck of cards? Answer: 1/2
What Examiners Usually Test
- Ability to calculate probability using fractions, decimals, and percentages.
- Understanding of independent and mutually exclusive events.
- Application of probability in real-life scenarios and experiments.