Topic Details (Notes format)

How to Calculate Probability of Dependent Events

Subject: Mathematics

Book: Maths Mastery

Dependent events affect each other’s outcomes. The probability of both occurring is P(A) × P(B given A). For example, if you draw one card from a deck and do not replace it, drawing a second card changes the total card count, making the events dependent. If you want the probability of drawing two aces consecutively: P(first ace) = 4/52, then P(second ace given the first was ace) = 3/51, so the combined probability is (4/52) × (3/51). This concept applies in quality control, forecasting chain-of-event scenarios, and more. Understanding dependent probabilities clarifies how sequential conditions shape real-world outcomes.

Practice Questions

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