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.

Illustrative background for Probabilities add up to 1Illustrative background for Probabilities add up to 1 ?? "content

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

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium