What Probability is
Probability is a measure of how likely it is that something will happen. It is expressed as a number between 0 and 1, where 0 indicates that an event will never happen and 1 indicates that the event is certain to happen.
Steps for calculating probability:
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Define the sample space: This is the set of all possible outcomes for the event.
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Determine the event of interest: This is the outcome or outcomes that are being considered.
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Calculate the probability: The probability is the number of outcomes in the event of interest divided by the total number of outcomes in the sample space.
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Express the answer: The answer should be expressed as a decimal between 0 and 1, or as a percentage between 0% and 100%.
Examples
- Estimating the probability of an event occurring such as the probability of a coin landing on heads after being flipped.
- Calculating the probability of winning a game of chance such as a lottery or a slot machine.
- Determining the probability of a certain outcome in a survey or poll.
- Calculating the probability of a certain stock price movement over a certain period of time.
- Estimating the probability of a medical diagnosis being accurate.
- Estimating the probability of a certain weather event occurring.