5.1.4

Sum of Probabilities

Test yourself

Sum of Probabilities

If all the possible outcomes of an event are listed then the sum of the probabilities of those events will be 1.

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Probabilities add up to 1

  • For any event:
    • P(event happens) + P(event doesn’t happen) = 1.
Illustrative background for RulesIllustrative background for Rules ?? "content

Rules

  • The probabilities of a set of outcomes add up to 1 if:
    • All possible outcomes are included
    • Only one outcome can happen at a time.

Jump to other topics

1Number

1.1Place Value

1.2Factors & Multiples

1.3Operations

1.4Fractions, Decimals & Percentages

1.5Growth & Decay

1.6Measurements & Units

1.7Accuracy

2Algebra

3Ratio, Proportion & Rates of Change

4Geometry & Measures

5Probability

6Statistics

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