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Calculate probability for single events, combined events (AND/OR), and complements. Shows formulas and step-by-step probability computation.
Probability is a branch of mathematics that quantifies the likelihood of events, expressed as a number between 0 (impossible) and 1 (certain), fundamental to statistics, science, and decision-making.
Probability
0.3000 (30.00%)
P = 3 / 10 = 0.3000
Formula
P(A) = Favorable Outcomes / Total OutcomesP(A) = Probability of event A occurring
P(A ∩ B) = Probability of both A and B (intersection)
P(A ∪ B) = Probability of A or B or both (union)
Worked Example
Rolling a 6 on a fair die
Did you know? Probability theory originated from gambling problems posed to Blaise Pascal and Pierre de Fermat in 1654. Their correspondence is considered the birth of modern probability (source: MacTutor History of Mathematics).
Sources
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Differentiate polynomial functions with step-by-step power rule application.
Solve C₁V₁ = C₂V₂ for any missing variable in solution dilution problems.